Ask HN: How much recurring income do you generate, and from what?

444 points by marioluigi ↗ HN
The last two threads by the same name got a lot of attention (and a lot of love from patio), but seeing how its been over a year since then it would be interesting to hear from new people (HN userbase is ever growing) and also get updates from some people who posted in the previous threads.

Previous thread: https://news.ycombinator.com/item?id=4467603

Previous to Previous thread: https://news.ycombinator.com/item?id=2567487

440 comments

[ 3.7 ms ] story [ 338 ms ] thread
I didn't post on the last threads I think, but I have had some modest success with passive income, was making up to 700 euros a month 2 years ago, this is down to 130 euros a month now. Still not too bad considering I haven't really touched the site for almost 2 years. But my heart isn't in that kind of projects anymore. Passive income is a bit overrated in my experience.

Still nice to get a small check at the end of the month.

The site in question is http://www.giftcertificatefactory.com, it provides printable gift certificate templates.

EDIT: I should add the money comes in from Adsense. I tried other monetization schemes as described there http://www.sparklewise.com/my-first-passive-income-project-o...

Nice site. Has the income come down due to a reduction in traffic spend or just a loss in rankings due to reduction in freshness metric wrt SEO or any other reason?
He mentioned it's probably seasonal. All the traffic he gets during non-events are people who have friends with a birthday soon.
My site got slapped by Google Penguin update, lost 90% of its traffic and never really recovered. It's going down steadily now for some time.

As for the Google penguin update drop in rankings, it might have been a stale content penalty, or a devaluation of spammy links - I wrote manually lots of articles for supposedly respectable article directories pointing back to the template website to go up in search engine rankings and it worked well for some time.

The idea was to extract myself of this process at some point since it was painful to write not very interesting articles. But didn't get around doing it, or outsourcing it.

My site got slapped by Google Penguin update, lost 90% of its traffic and never really recovered.

It's funny how you don't really build websites anymore (did we ever?), you build sites for Google's search engine.

Even thought websites are conceptually different from writing a Photoshop plugin, in reality? Not so much. You're just as dependent on Google as you are Adobe, it's just hidden.

Would you consider passing it on to someone else, with a view to getting hands off royalties for a time. Or would you just want to sell it and have it clear cut?
After reading your post last year, i started my own niche website making iphone app templates (easily googleable). I ended up taking it to roughly $3k/month in revenue and have just sold it to a private company.

Thank you for writing that post.

I generate around $2,500/mo. I operate a company which mines poker data and have a couple of partners, plus some large server / tech / support costs. No-one is full time on the business any more as after Black Friday there isn't a lot of $ in poker: http://hhsmithy.com/
This is fascinating. It took me a while to discover the purpose of subscribing to this data, and I finally found it at https://www.hhsmithy.com/tour

"Finding the best tables to play on is impossible without up to date statistics and data on the player pool and consistently playing pots against opponents with no reads or statistics is a sure fire way to lose your bank roll fast."

How do you harvest this data? Do you use player bots?

Also, you have a typo on that page: "Your on the cut off with AJo and a player under the gun has opened". Should be "You're".

The data is used with 3rd party tools that scan tables, find the best seats, display statistics etc. The most popular tool is holdem manager (http://www.holdemmanager.com/). After buying data off our site you can import hundreds of millions of hands and have detailed info on almost every player on a poker site (how often they raise, fold, call etc etc). If you also scan tables and sit with the "fish" (recreational players) then you will win a lot more. One day I'll write a blog post about what online poker is really like (game theory, tools, and statistics).

On the tech side its some fully reversed clients that we just have linux command line clients which connect to sites, and other sites its a ton of Windows XP VM's which open tables and observe. At the heart of it all we have some command servers which handle distributing the table load, parsing and aggregating all the data etc. Each day we "mine" over 10 gbs of data zipped and at peak times can be watching over 10,000 poker tables. It's pretty nuts that it somehow all works.

And yeah, lots of typos :-O

It's crazy to me that online poker companies make this information available. Shouldn't tables be private or something to stop this?
Yeah, a few sites have made it so you can't observe tables but most sites allow it. You'd have to ask them why but I assume that casual players like to observe before depositing and they don't want to scare away the casual players (who are the life blood for a poker site).
If you, like me, are wondering what "Black Friday" is in the context of poker, it refers to United States v. Scheinberg: http://en.wikipedia.org/wiki/United_States_v._Scheinberg

United States v. Scheinberg is a United States federal criminal case against the founders of the three largest online poker companies, PokerStars, Full Tilt Poker and Cereus (Absolute Poker/Ultimatebet), and a handful of their associates, which alleges that the defendants violated the Unlawful Internet Gambling Enforcement Act (UIGEA) and engaged in bank fraud and money laundering in order to process transfers to and from their customers. (...) After the indictment was unsealed on April 15, 2011, a date quickly dubbed Black Friday by the online poker community, PokerStars and Full Tilt stopped offering real money play to their United States customers.

what are some of your main competitors? i know tableratings was big in the past but then got blocked out by pokerstars (and apparently now ftp as well).
hhdealer.com, hhmailer.com, handhq.com are the major competitors. After Black Friday there are lots of small localized (especially Eastern Europe) competitors. Poker Table Ratings also provide search, and we built something to do that too (PokerCloud) but ended up selling the tech and domain.

Its an interesting world though where only us, table ratings, and mailer actually do mining (as far as I know) and we sell at wholesale prices to some of the other resellers. And then of course there are lots of people who buy hands and without our consent resell them through forums, web sites etc and that is an ongoing battle. We all have interesting ways of marking our hands so we can track them back to users and ban them.

$800 a month for support of a few scripts i written 3 years ago. Drop in the bucket but still keeps me very motivated doing any work for that customer (and this is the only work at all that i still do myself, not my employees).
I've made about $3k a month in semi-passive income from my codecanyon portfolio in 2013. I call it semi-passive income because I have to spend some time on support each day, but it usually doesn't take more than 30 minutes.

EDIT: My portfolio http://codecanyon.net/user/23andwalnut/portfolio

I sell on codecanyon as well though only make around $300 a month right now. I have almost the same number of items as you do yet can't seem to get the visibility. Do you have any tips you can share?

Also, completely agree about the semi-passive! Lots of questions to deal with daily.

In my experience quality sells. Quality code. Quality feature set. And most importantly, quality design. I think a lot of items on codecanyon neglect the design aspect and therefore don't sell as much as they could.

Also, I've been somewhat lucky in that almost all of my items have been featured. This probably has something to due with how much time I spend on design - at least 40% of my total development time is design. Feel free to email me with a link to your portfolio if you want some specific pointers...

You're probably right about the design side of things, mine is definitely lacking I just have zero ability in that area.

I've send you an emails, thanks!

I make it a point to make sure the featured items look really yummy. ;)
How do you decide what sort of thing to make in order to sell well in a marketplace like this?
I build things that scratch a personal itch. If there's a product that I need and I can't find a suitable existing product, I build it and sell it, because I assume other people also have that need. That's how Duet was born - I wanted a self hosted project management app that was functional and beautiful. I couldn't find one, so I built it myself...
I make around $5 to $10 a day from my site http://tunes.io I haven't put any effort into marketing it or trying to monetize it other than adsense. Maybe I should be trying harder!
I was about to post, "How do you make money on this?" And then I remembered that I use AdBlock. D'oh! I paused it and refreshed a couple times.
Yeah I use adblock too - even on my own site ;) I was thinking maybe I would make a tunes.io android app and sell it for a buck just to see what happens.
I'll tell you what will happen. I would pay for it! tunes.io is great!
How much traffic do you receive a day?
About 400 - 500 visitors a day. CPM is ok compared to other sites I've run adsense on. People seem to like the site.
How are you attracting those visits, ads, word of mouth, etc? I run tubalr.com and have considered ads but am worried it will scare off the users I have. My traffic is a little more than what you're running... but its going down day by day.
My traffic is pretty much direct/word of mouth. I haven't done any advertising, just a few links on places like HN. The problem with a YouTube video site like tubalr is you can't use adsense unless you have a lot of added content and you are competing with the ads in the videos anyways. And in my experience other ad networks have really bad CPM rates. So you probably have to find another way to monetize the site, which is tricky. The sad fact is that music/video sites while fun to build are a hard way to make money (having built a few myself).
Instead of ads, I decided to try affiliated "buy this song on x site" buttons on my site (www.tunecrawl.com) under each song. It generates so low income, however, that I would have removed it a while ago if users didn't find it useful. Might be worth a try to see if you have the same result. If nothing else, it adds some additional functionality to the site and is easy to set up. I honestly think you could get away with some well placed ads on tubalr, though.

Great redesign, btw!

I like yous site. Do you have a white label version of your site? I want to build one for a completely different vertical.
You could sign up to the iTunes and Amazon affiliate programs and then link to where users can purchase the songs. The nice thing with Amazon is once users click through to Amazon from your site they are cookied and you will get a commission from whatever they buy. They could come in on a 0.99 download but they end up buying some underwear and a book and you get a cut of it.
A better question I'd like to read is "Good ideas for recurring income".
And the only sensible answer you would ever receive should be "anything that people want to pay repeatedly for" :)

My point being. I don't think anyone would give you a specific idea for recurring income cause then they would go ahead and do it themselves.

I might be wrong but I doubt it.

Any idea which hasn't been proven to work already is practically worthless. You're better off looking at cases of existing successful passive income and emulating those.

Then, you can tweak it, one small change at a time.

Sort all the answers to this topic by revenue and your question will be answered.
Good ideas to make money are a dime a dozen -- just look at android forums.. there are a million ideas that could make money..

Seeing real examples can sometimes give a better idea of what an idea is really worth, with real numbers, not what a concept could be worth IF(and a BIG IF) people really want to buy it, or visit it, or download it..etc... 1 Real life case study is worth 100 ideas for apps/businesses.

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Thanks for sharing the past discussions. The more often we can talk about this, the better off the community can be.
First link is to 9/3/2012, not 2013 as labeled.
I'm just going to post this question every day, since it seems to be so popular on this site : )
Nil.
likewise. :-(
Can I ask why? Is this intentional because you're busy doing other stuff, or because your efforts have yet to be successful?
working full time job, don't really have any great idea. fear of failure and over thinking leads to paralysis.
I wrote a guide to integrating Stripe payments into Rails applications that expands greatly upon the 10-minute quick-starts[1]. It launched a little over a month ago and has generated more than $10k. I'm expecting that to drop quite a bit going forward but I'm still hoping for ~$500 in monthly revenue.

[1]: https://www.petekeen.net/mastering-modern-payments

How do / did you market it? As it seems as if you're only hosting it on your personal website? How do people find it?
I set up a mailing list right at the beginning (there's a signup link way at the bottom of the landing page, need to make that more prominent) that generated quite a bit of interest. My website by itself generates a decent amount of traffic as well. It's also been featured in a few podcasts and email newsletters which generate traffic and sales.
Thanks for the info! Did you ever consider also selling it via a couple of ebook sites?
I've been considering selling on other sites (maybe Amazon) and/or doing some limited affiliate deals, but I haven't put any serious work into it yet. What sites were you thinking of?
in the millions/year and growing. managed hosting and cloud hosting.

the hard part is keeping the profits as we learn to scale the business.

I have $200-$300 in (mostly) eBay and (less so) Amazon affiliate income from a message board and news site I run, both about a band.
I make about $500/month from my iOS apps. Considering how much time I put into them I can't say it's really been worth it yet but I plan to at least upgrade them for iOS 7. They did open the door for some unsolicited contracting work though.

http://www.plastaq.com

TL;DR: The top of our funnel is fine, and our app is making money, but it's not "easy money" and our trial to paying customer sign up needs some serious attention.

I run a HR app for SMEs called http://www.staffsquared.com. We're making a comfortable 5 figures each month.

We're reinvesting this income back in the product either in the form of new functionality (paying programmers) or advertising (paying Google Adwords). We've increased our Adwords spend, invested in SEO (on page and off page) and a recent redesign saw a decrease in bounce rate and increase in trial sign up rates.

Our site visit to trial sign up rate for the last five months looks like this:

April: 13.02%

May: 12.37%

June: 13.76%

July: 15.61%

August: 16.46%

Our bounce rate for the last five months looks like this:

April: 39.54%

May: 40.06%

June: 37.21%

July: 32.8%

August: 31.17%

So both of those top end of the funnel stats are moving in the right direction.

Our free trial to paying customers is the area we're really focussing on at the moment as it's really not high enough. So we're re-targeting accounts that have expired to find out how we can serve them better and tell them about new features. We're also working hard on our onboarding stuff (the type of stuff you'll read patio11 talking about) including more intelligent automated e-mails based on the status of their account at a point in time.

Happy to answer any questions you good people might have where I can...

This is very interesting. Thanks for sharing and best of luck!
Please share anything you can about how things go in the future. I'd love to see how your dunning emails turn out. Can you also share some background? When did you start? How many people are on your team? What kind of initial investments did you do?

Really awesome to see people being so transparent about how they're doing.

By the way, if you ever want to write any blog posts and cross-post them to Lifestyle.io [0], we'd be happy to have them.

[0]: http://www.lifestyle.io

If there's a demand I'd be happy to share our lifecycle email updates...either way I'll be sure to keep track of our progress so I can report on it from time to time. Getting the onboarding process exactly right really is a combination of art and science (mostly science).

We launched Staff Squared about 18 months ago, it was originally an internal app that I used at my software company http://atlascode.com that we realised could be useful to other companies. We bootstrapped the app from the outset and haven't taken on any investment as I wanted to see if we could make this thing work first. Turns out it's possible to make a profitable business from it but it's by no means easy.

I do pretty much everything...sales, marketing, support, QA, specifying new features, and so on. My team of devs at Atlas consists of four full time .Net developers. I now also have a part time person who helps me with marketing, newsletters, copywriting and design. Our office manager assists with some of the support requests we receive and manages our oLark chat on the site...

We're looking to grow now and take on more developers as I'm finding it hard to balance the client work we've got at Atlas and keep Staff Squared "fresh". All good problems to have :)

I'll check out lifestyle.io and see if I can contribute something of use to that community. Thanks for your interest!

How do you market StaffSquared? You mentioned SEO and ads; is this your main source of customer acquisition?
We're currently number 1/2 for "HR software" (at least on google.co.uk) and so we get a lot of traffic from that. I'm working on getting us to rank for HR Systems which gets just under half the amount of traffic as HR Software.

We have a limit of £30 per day on PPC. It drives traffic to the site but I'm still getting under the hood of whether it delivers real ROI.

We get a lot of interest in our app from the Chrome web store. I think a lot of people overlook that as a (free!) place to market their software. They have a whole section dedicated to HR software and the majority of the time we're featured at the top. We're going to get listed on the Google enterprise marketplace soon too.,

A bunch of other stuff we do includes:

* Advertising on various HR blogs

* Partner marketing - I could write a whole post on just this topic, it's a big undertaking

* Writing guest posts

* We're trialing influads.com at the moment, which is an ad platform. Again I'm not sure if we're getting value from that just yet...

The one thing we've not done to date is press releases. We've performed exactly zero PR for the app, but that will change once we complete a few super cool features we're working on that I feel will set us apart.

Hope that helps!

EDIT: Formatting

The chrome web store is a great idea. Does the chrome app provide any additional functionality? Or is it primarily a link to the web app?
When people "install" the app from the Chrome web store it just puts a link in their browser. That's it.

In the Google marketplace it's a bit more advanced, and you can integrate with Google authentication for sign in, and with documents for document sharing and so on.

Apparently "SME" means "Small & Medium Enterprises".
Ah yes, you guys refer to it as SMB I believe?
No, I don't use either of those terms often enough to have an acronym for it.

(FWIW, apparently "SMB" means "Small-to-Medium Business".)

Thanks for this clarification, as I'm used to SME meaning Subject Matter Experts (which also applies to the product).

BTW, the Staff Squared homepage is really impressive! My eyes are directed to all of the right places on the page to sign-up and learn more. I also like that clicking the Roadmap link on the footer leads directly to the Trello project page.

Thanks so much for the feedback, really nice to hear that people who haven't seen the site before think we're doing it right :)

For the record, if anybody thinks we've made a huge mistake on the site I'd love to hear about it!

Thanks for the info! Just a heads up: seems like your Twitter account is suspended.
Yeah we know, happened yesterday. Thanks for the heads up..

To explain: I was experimenting with an app that it turns out breaks the twitter rules and so they've suspended us. I'm talking to Twitter now about getting us unsuspended.

What was the app? Tweetadder or something?
Followgen? Experimented with it and although provided some value it ultimately got our account permanently suspended.
Holy shit really? Yeah it's followgen...I've e-mailed the owner and revoked his access to our twitter account.
I think you might consider changing some of your cartoons so that a Woman is running the business. I think it's a bit strange[1] that it's the male character all the time.

I don't know if that's something that might turn off a woman, but it did sort of jump out at me.

[1]Full Disclosure:I only browsed through a few pages, I did not to a page by page gender analysis.

> but it did sort of jump out at me

wtf? This is the kind of shit we're tired of in Sweden. There is a woman talking and why would anyone care when they're out looking to buy HR-software?

Simon, Thanks for the great insight!

We are also targeting SMB sith a SaaS in a different area (sales): http://www.quotty.com.

We haven't still defined a strategy, but your comment caught my attention because we are facing the same issue. Your application is innovative, how do you announce it? I figure that hardly somebody will search for an application like yours that nobody figures exist?

In summary where you get most leads: keyword search, organic search, partnership, ads placed in industry blog? Did partnership generate results? With other software? With distributors?

Another issue we found is that many users are too lazy ans inexperienced for the trial disert. I am conducting the following experiment: instead of immediately sending a free subscription-trial password, we ask for a phone number that we will call to make an interactive (remote) demo of the product using real client data, This has improved results, but elevated cost.

Don't you have the same training problem with new users?

I mine about .0015 BTC a day, a figure that has been declining consistently and rapidly.
Time to pony up the cash for your very own ASIC!
It might sound kind of obscene here on HN, but I'm making about 3500 euros per month, semi-passive from adult related site/community. It's subscription based and the content is user submitted (that's why it's semi-passive). Some moderation is necessary, as well basic user support, but overall - not so much hustle.
How did you break into this industry? I've done random work as a freelancer for a few different adults sites, but I've always felt like running my own was the real "money shot" as far as passive income goes. Can you elaborate on how you got started and how you keep an edge in such a competitive space?
I'm not really into the industry - my main income is coming from working for major brands in the ("mainstream") ad industry.

I saw the service of acquaintance of mine and what revenue he's making, so I though I can do better.

Generally, in this industry there's massive shortage of talent, ideas and innovation. This is a big opportunity for people who are delivering value in the "mainstream" startup scene and that was one of the reasons which made me try - you can get in and disrupt pretty easily if you think out of the box, which is not so hard in this context.

Most of the stuff is almost scam, the customers are threatened like idiots and technologically the year is 2002-2003.

There are people who say there's no money anymore in this industry and they're right - there's no money for people who are short on skills, ideas and execution, but there is huge potential for people who are coming from other "mainstream" industries.

My prediction is that lot of talented kids will enter this industry with great services - I see it as emerging trend at the moment.

Is technology really that behind? I mean redtube/et al are some of the largest websites out there and the blog posts seem to show a pretty high level of technology behind them although with a larger focus on cost than most startups.
99% of adult sites run on single servers using out of date PHP/MySQL scripts. Sites like RedTube, etc use newer technology, like at Confoo a dev for YouPorn talked about their stack and they use Symfony, Varnish and Nginx.
Can you please provide more detail regarding how innovation is lacking?
I've been curious because I was thinking of doing something that would host content; is it a legal nightmare if someone uploads illegal material? Is it common?
Yes, and yes.
Care to elaborate? How much risk is there to the site owner which accidentally hosts the content?
You'll want to make sure all models are of legal age, and that the person submitting it has the rights to upload the material. Yes there's DMCA clauses to live behind that help make such tasks easier but in adult DMCA is so widely abused that it's best to make sure your stuff is 100% legal and legit to stay out of trouble. Not worth the returns in my opinion.

Source: I have just spent the last 12 years in adult and recently just severed all ties with the imploding industry.

It depends, but overall it might be risky if you don't pay the necessary attention.

In my case - I've kind of outsourced it, but every user submission is being reviewed before it's published.

Which payment provider are you using? AFAIK most of them are very picky on the subject.
CCBill, SegPay and Achbill.
It's not obscene to work in the adult industry! Good for you for being successful at what you do. €3,500/month isn't something to sneeze at.
Congrats. What hosts are you running at? I haven't been able to find one that allows adult content
Thank you.

I'm using Webair at the moment, but you can check also Amerinoc and Leaseweb.

low 4 figures from real estate
Buying/selling? Renting? How long did it take to get into it, and what did you do previously if different?
Buy and hold. I had been patient and bought after the market crashed. I bought it in another state and put 25% down on a 4-plex. Rent pays my mortgage and I have money in my account every month. I would have tried to earn more money in order to purchase more.
Passive income? Online?

details ...?

For me it is passive, I have a property manager. I did all of my research online, met my agent over the phone after Googling. Did not visit the property before purchasing. I did a lot of research however...
It seems the big winner is Apple and Google. They passively collect 30% on the apps we spend months making.
Nothing about what Apple and Google provide for developers/App Store is "passive".
I suppose Apple devotes a lot of manpower and is very "active" in excluding all developers and applications outside of its walled garden.

Google is much different in that you have the option to publish on alternate app markets, or self-publish your own apps, of which Google gets a cut of $0. This lack of control over their own app marketplace is probably the cause of Google's flagging stock price and Android's failure to effectively compete with iOS in the mobile market.

>"the cause of Google's flagging stock price and Android's failure to effectively compete with iOS in the mobile market."

Was your comment sarcasm, or just terribly misinformed?

"Flagging" stock price? You mean the one that's hovering around all-time highs? Android's "failure to compete" with iOS for the mobile market? With 80%+ of global market share?

Look, the fact that these two companies happen to be be geographically located in resource-rich land is in no way a merit. Apple pretty much did a survey and struck the iPhone, which has been guzzling up ever since. Google bought some land from Herman J. Android and it turned out to have a large natural deposit of everything that has been coming up ever sense in the form of its mobile offering.

But make no mistake: if you had put a stick in the ground you would have seen the same result, provided you were as geologically fortunate as these two lucky suckers.

I disagree. Nobody at Google would have a job if it wasn't for Adsense/Adwords, which hasn't changed since the Goto.com days. It's a fancy click counter script paying everyone's salary. Search = content to sell clicks. You could fire 99% of everyone at Google and they wouldn't lose one penny of profit.
So the App store infrastructure, support, etc just built itself automatically? The entire eco-system would not have been possible without them making it.

I've been an App developer for 4 years now and have no qualms with apple taking the 'passive' 30%

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I was just talking about Google. Sorry if my comment was vague and off on a weird tangent ;-)
And they didn't even put in any investments or work hours ;)
How much of our time do we spend managing their servers, security, payment gateways, etc...?
It's like oft-touted maxim during the dotcom era: those that made money during the gold rush were selling shovels to those digging for gold.
I make enough to buy a Frappuccino from day to day, mostly from a reaction gifs application on the App Store : https://itunes.apple.com/us/app/my-reaction-when/id632831985...

By the way, all in-app purchases are free today and tomorrow...

How long did it take you to make this app?
It took me maybe 3 weeks (3 to 5 hours a day) but I experimented many solutions (APIs, sharing, Vine...). I used RubyMotion and I had prior experience with the iOS environment.
$2500/mo from AdSense on http://coverphotofinder.com/

Zero-maintenance, which is nice.

That is insane! How did you attract users in the beginning, and do you use the same strategy now?
You know, what I would love to know is how you attracted the initial audience. This stuff is always so easy to make, but my past attempts never really got enough traffic boost. I'm wondering how you got over the 'plateau' (which in my experience seems to be ~1000 visitors a day.
This site forces you to login via facebook and then sell all your friends by forcing you to allow it to spam to all connections, thus promoting itself.

Dirty "viral" tactic.

seems Google, Facebook, Yahoo etc. have been using this practice for decades.
Sorry, forgot about this thread! We were first-to-market (may have had insider information about the Facebook Timeline launch...), and got on Mashable. Spread through the blogs and hit #1 on Google for "Cover Photos". We've stuck that #1 spot and it's where 80% of our traffic comes from.
.. but where are the ads? I don't see any.

EDIT: Oops. I've had an ad blocker installed so long I forgot it even existed. :-) Leaving my comment up though to save this discussion thread in my history. Nice site!

Around $40-50 from admob and amazon affiliate links. It pays for my netflix. I originally set myself a goal "just to see" of buying myself one pint of ale from a pub over the course of a year for app sales/ads - not exactly ambitious but I thought i'd end up at best shifting a few cents a month.

I had already an app on android with ~3000 active installs for doing simple shopping look ups. I changed it to throw in some affiliate codes and fixed a crash and updated it approximately 18 months ago now and haven't made a single update.

It's next to nothing but it encouraged me to look more into at least trying things out for myself - I would never have thought (and still can't) it would be any more than a personal exercise. If I look at it as "free netflix for 2 years" then it's a real thing to me and "means something".

About €1000 from a subscription based web analytics niche thing and another €2500 from my wife as she works for the government.
I make around £400 per month on tutorial videos for music production applications. It used to be more like £1000, but I've neglected the site in favour of pursuing programming (so I can make my own music applications, instead of talking about other peoples').
Few years ago I wrote a solution manual to one of my text books (half of it was part of the assignments). I sell it on Amazon for $30 for pdf download. Been making around $200/month.
How much time did you put into this upfront? Seems like the most "passive" item in the entire thread so far. Can I ask what book this is for? whats the lifespan of a solutions manual like this? Have you been selling it for several years or does it obsolete itself in sync with the aggressive textbook versioning schedules?
I guess I am lucky that the text book still gets prescribe in some universities. I also think there is no other version of the text (I need to check that) I do not maintain it at all. And like I said, I solved most of the questions as part of the assignments and later worked out the left over ones, packaged it into a pdf.
When my professors found out that there was a solution manual floating about, they changed the textbook. Apparently all of the student's answers started looking the same.
Between $1450 and $1650 a month from ads on Android apps. One app does about $1100 a month, another does $325 and the rest collectively maybe $150.
Do you think ads are a better way to make money than charging for the app?
I am also wondering about this. I have an app selling at $0.99 and make a couple hundred per month in sales. It's hard for me to project how much ad revenue I could make, especially since I don't know how many additional people would use it if it were free.
The beauty of Android is how easy you can create a new developer account and test out some ideas.
It depends on the app, the needs and desires of the development team etc.

I do not focus on game apps, but when I did a few the ad click through rate was very low for them. So if I was doing games, I might look for a different revenue model. Pay apps, freemium etc.

It depends on the specific app. Some are better with an ad based revenue model, some are better when sold. European car navigation apps used to sell well. On the other hand, some simple flashlight apps with ads have also done well. So you can make money either way, and which way depends on the circumstances.

I should also say I have seen some new developers release their first app as paid and they make few if any sales. Unless you already have existing business knowledge of a specific area, for most new Android developers, they are usually better off releasing their first app quickly and for free.

Can you possibly share a little of the stat (impressions maybe) that generates the $1k+ ?
Usually over 1.5 million impressions a month.