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Show HN: Sudoku with 0 Bells or Whistles

48 points by joelalcedo ↗ HN
Hello HN,

I've created a new Sudoku app for iOS and Android that prioritizes simplicity and privacy. It's free to download and use, and I'd be grateful for any feedback or suggestions.

Features:

> 4 difficulty levels, accessible at any time

> No personal data collection of any kind

> Clean, minimalistic design that focuses on the game

> Takes up significantly less space than other popular apps (by a factor of about 10x)

> Minimal use of advertisements

I was frustrated by how many of the popular Sudoku apps feel excessively over-engineered, consume a lot of storage space and some that even collect unnecessary personal information, like location and contacts. So I put this app together without any of those things (using flutter).

Links:

iOS: https://apps.apple.com/app/sudoku-puzzle-palace/id1668683822

android: https://play.google.com/store/apps/details?id=com.kingfisher...

Here's a screenshot of the main app page: https://imgur.com/a/FbCf2IJ

Thanks for taking a look and happy solving!

48 comments

[ 3.0 ms ] story [ 108 ms ] thread
y-curious
I play sudoku daily and will give it a DL. That being said, I already see a big gripe from the screenshots: No pencil tool. At higher levels, it's critical. Will report back :)
y-curious
Yes: No pencil tool, no active checking. Also, you should trickle free hints at people instead of forcing an ad click, that's how you get 'em.
joelalcedo
Thanks! A pencil tool should be straightforward to add. Do people usually use a stylus for these purposes? Someone else mentioned the ads, I can easily embed some mechanism to remove them.
y-curious
You can keep ads, but the sudoku app I use gives you a few hints for free, first.

Pencil tool is usually a toggle- you default to `pen` but toggle `pencil` mode to fill them out. Look at the top android sudoku app's implementation, it's slick.

joelalcedo
That's helpful, thanks so much!

What type of hints are most useful from your POV? Are they more direct (i.e. here's a free box in case you are stuck), or more suggestive (e.g. "Pay attention to the naked pair in the third grid")?

With the latter, striking a nice balance between hints which are simple to articulate without esoteric terminology is important.

Really appreciate the pencil mode pointer, I'll check it out.

joelalcedo
I finally got around to this. Here's a screenshot of how the new "pencil mode” looks in the latest version of the live app.

https://i.imgur.com/QrSqNwH.png

By tapping the same box twice, pencil mode is activated. You can enter any placeholders you like in the box.

Tapping the box again disables pencil mode, and the inputs you placed will remain in the background if you need to refer back.

ebiester
Honestly, look at Cracking the Cryptic's app. It's all hand generated puzzles so it's much more expensive, but their app is definitely the best.
joelalcedo
Thanks, I will take a look. Really appreciate the suggestion.
paranoidxprod
Really like the look of this based off images. Just downloaded on iOS and going to give it a try during my lunch. I've pretty much refused to play Sudoku on my phone due to the reasons you've listed. They all seem to have either massively intrusive ads, or they are ridiculously over designed. I'm looking forward to trying this out!
joelalcedo
Thanks! A couple people on here have mentioned they like their gameplay to come with 0 advertising so I will remove ads altogether as a feature. Would love to hear how the gameplay went and if you have any suggestions.
paranoidxprod
Personally, the banner ads at the bottom of the screen and ads for hints don't bother me at all. Most apps I find seem to have a system where you have to watch an ad after completing a puzzle or when you make a few incorrect guesses, which bother me. I do always appreciate when apps have an option to turn of ads for a buck or two so I'm sure others would appreciate that too. I'll be sure to check back in once I get a chance to play through a full game!
joelalcedo
Gotcha and yes - when I started playing, a few apps asked for location permissions, and served ads up before I even started playing. The only ads that are served here are one at the bottom and one when a hint is requested.

Few items to add onto the list thanks to this thread, really appreciate it.

Melkor765
For anyone looking for a great open source Sudoku app with no ads: https://play.google.com/store/apps/details?id=org.moire.open...

This looks great but I was sad to see advertisements and consider that a bell if not a whistle. I would pay a few bucks for this if it could match the features of the above with this clean visual style.

joelalcedo
Hey, thanks for that! I can implement some type of feature for people who want to get rid of ads altogether for a buck or two. Appreciate the suggestion.
TN1ck
Shameless plug: I built an open source, completely free, no ads/tracking whatsoever sudoku with a lot of bells of whistles. It’s only web based, so no native apps. Find it here: https://sudoku.tn1ck.com/

Source is at https://github.com/TN1ck/super-sudoku if anyone is interested

ad404b8a372f2b9
Very cool, feature request if you ever work on it again: numpad support, a way to toggle-off the row/square highlighting when you select a cell, del key to empty a cell.
TN1ck
I thought I added numpad support, will have another look. I’ll add a setting to disable the highlights next week, thanks!
endemic
Thanks, I personally find that for these sorts of puzzle games, browser-based is the way to go. I don't particularly want to install yet another app that is a black box in terms of network communication.
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joeframbach
I'm not able to auto-generate notes, then delete some of them.

e.g., a row contains the auto-generated notes:

    [1,2,3,4,5] [1,2,3] [1,2,3] [1,2,3]
I can't remove 1,2,3 from the first cell.
TN1ck
Yeah they conflict, haven’t really worked too much on how to resolve this. I mostly did the auto generated notes as I found them cool, how did you expect them to work? Currently they are live updating, but I guess a one of action might more sense?
joeframbach
It's tricky for sure to do it without complicating the interface. You'd need separate concepts of allowed notes and denied notes. If I say a not can _not_ appear somewhere, then it should purge that note forever. But how to portray that concept to the user?
angus-g
I thought it might work a little like the NYT sudoku app: placed numbers delete candidate notes automatically, but you can also manually toggle candidates on/off. I guess a once-off generation would probably work to achieve this?
karaokeyoga
Awesome project. Is there a way for the app not to tell me when I made a mistake? I must be doing something wrong as I'm not able to toggle this setting on/off.
INTPenis
What about SudoQ[1]? That's the one I used many years ago during my sudoku phase. It's open source, very simple, accepts "drawing" input as well as regular keyboard.

1. https://github.com/timo-a/SudoQ

Zanni
Scaling seems to be off for iPads. Downloaded but can’t even try it out because the start button is (mostly) off screen. 11” iPad Pro, 2nd gen, iOS 16.2
partusman
Looks fine on my 2022 11” iPad Pro.
joelalcedo
Thanks for the tip, I'll take a look.
joelalcedo
I found the issue, led me to realize my scaling across all devices needed a rebuild. Should be fixed in the next release (submitting tonight). Really appreciate it! What features would you like to see for the iPad? More real estate on the screen lends itself to interesting options.
shaneos
Another shameless plug - I built a multiplayer sudoku game where you and multiple others can compete to finish the game first. It's a web app at https://countdoku.app/
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ufo
The Sudoku app I currently play is this one: https://f-droid.org/en/packages/org.secuso.privacyfriendlysu... (found by searching Sudoku on F-droid)

My only beef with it is the difficulty. I feel that Hard is easily solvable without guessing but Challenging invariably forces me to resort to guessing at least once. (I believe that's the logic their underlying library uses). How does your app determine the difficulty of the puzzles?

psoots
Honestly, there's nothing better than the Cracking the Cryptic app for sudoku, called "Sven's Sudoku Pad." People who love sudoku have congregated around that channel. It's updated regularly and there are a lot of puzzles that can be imported into it. It gives you very helpful pencil mark controls including colors and differently placed marks. There really just hasn't been another app that compares to the level of production for this Sven's.
scottmsul
Also the novel rulesets make it so much more interesting than vanilla sudoku. Oftentimes the puzzles have really abstract/mathematical/beautiful break-ins. Definitely adds a lot of variety and replayability.
OkayPhysicist
My go-to for pen-and-paper style puzzles (including Sudoku, but mainly Loopy) is Simon Tatham's Portable Puzzle Collection [0]. It's extremely portable open source C, so if you can compute on it, you can probably compile STPPC for it.

[0] https://www.chiark.greenend.org.uk/~sgtatham/puzzles/

yetanother12345
Two comments:

     $> aptitude show sudoku
     $> sudo apt install sudoku