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If you want to blow the mind of a non-tech person. Show them a high capacity MicroSD card and tell them how many 1’s and 0’s it can reliably store.

A 2TB MicroSD card really is a modern marvel in engineering.

how many can they store?
Approximately sixteen trillion. I suspect that number is not really comprehensible to a large population though.
so the grains of sand on TRAPPIST-1e
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> Grains of Sand: If you were to count grains of sand, assuming roughly 10,000 grains per cup, you would need about 1.6 trillion cups of sand to reach 16 trillion grains.

Math is not ChatGPT’s strong suit.

It’s enough to store the name of every human being that has ever lived.
If you were to count those at a rate of 1 per second, it would take about half a million years.
16,000,000,000,000
1 Byte = 8 bits

1 KByte = 8 * 1000 = 8 000 bits

1 MByte = 8000 * 1000 = 8 000 000 bits

1 GByte = 8000000 * 1000 = 8 000 000 000 bits

1 TByte = 8000000000 * 1000 = 8 000 000 000 000 bits

2 TBytes = 8000000000000 * 2 = 16 000 000 000 000 bits

All values approximate.

I have a frame of various media over the years over my desk including a 5.25" floppy, a 3.5" floppy, ZIP disk, CD, Blu-Ray, SD, microSD, etc.

As a technical person, my mind keeps getting blown.

That’s a really nice idea. Maybe I will steal it :)
It's a fantastic and quick project!

I use two layers of thin black foam. The top layer of foam sheet has cut-outs for the various types of media except microSD card, which is held in place with a small dab of glue. They're pressed against the glass and has survived 2 moves without issue.

That doesn't mean much though.

How about when you tell them it can store 38 seasons of TV shows in HD?*

Or 40 dual-layer Blu-Ray discs?

Does it seem like a lot or a little?

*Assuming 4 GB per 60-min drama episode in 1080p, and 13 episodes/season, all of which is pretty ballpark.

with most laypeople streaming, they don't really have a sense of how much space a season of tv shows is. you need something more relatable, like photos
There was a thread here the other day about how everyone just streams everything, and nobody knows what a file is any more. Why would someone know how big a photo is? They're all on Google anyway.
not everyone has google/icloud sync on. people run out of space on their phones all the time.
I think the obvious Americanized measurement here is "number of football fields covered by 4x6 photos".
Or almost 1 copy of the Oppenheimer director’s cut
Wait, if one microSD card holds more than a year's worth of TV shows for an average person, does that imply paying $10/month for unlimited streaming is a really stupid idea? Granted it's not about paying for the recording medium, but still.
Depending on if they are old enough to remember floppy disks, tell them the tiny card holds as much information as almost 1.4 million 3.5 inch floppy disks (assuming 1.44mb each). If you pile those up, it would be about 4.5 km high. Or if you take the 720kb kind, your pile would be as high as Mount Everest.
Holy shit that’s a great way of putting it.

I’m not double checking the math but that’s insane, 1.4 million, insane.

I am old enough to have used 5 1/4 inches floppies on PCs running MS-DOS, 3" microdrives on ZX Spectrum 3+, and tapes on Timex 2068.

One of my teachers broke the compilation record of compilation submissions per day, on the computing center, with punched cards.

On my first trip to a computing center of the post office during high school, they still used punched tape.

The modern SD cards are indeed a wonder.

Yeah this is the corollary to "use boring technology" - at some point, jump.
They could put the capacity of every 3.5" floppy ever made in a suitcase full of microSD cards.
A wild guess of 3.5" floppy production is 30B. So you need 21,428 2TB micro SD cards. A 15mm x 11mm x 1mm you need 3 1/2 liters.
The bandwidth of a station wagon hurtling down the highway grows every year.
Sneakernet remains undefeated. https://what-if.xkcd.com/31/
>> "A solid-state laptop drive weighs about 78 grams and can hold up to a terabyte."

Amazing how we went from 1TB 2.5 inch drives to 8TB m.2 drives and 2TB microSD cards in 11 years. And it would be more like $7k in 4TB drives than $130k. Put $130k of modern drives in the same shoebox and you're probably into the petabyte range. Go to the then-top of the line microSD milk jug and it's getting up there with these 2TB cards.

"I could have a bodycam record everything that happens to me for a whole month, 24/7, in high-definition and store it on something smaller than my fingernail."
HD (1080p) video @ 30fps is from 130-149MB/sec

2TB / 149MB = 13,422 minutes == 223.7 hours == 9.32 days

I'm being facetious of course but I was surprised by just how much storage space I needed to record security cameras. I have a mix of 4k & HD, and 10tb doesn't even get me a month of 24/7.

YouTube’s 1080p is 5 megabits per second, not 130 megabytes per second.

So 2TB lasts 37 days, meaning blowski is right.

Of course powering that bodycam will be a different matter.

Of course this is all academic: the file size depends on the codec, ie how much you want to trade power for space. YT/Netflix/etc obviously trade for file size very well. But a body-worn device isn't as capable.

Take the Axon Body 2 as an example, the gold standard for police bodycams. According to its specs [0] it'll record 12 hours of 1080p video on its 64GB internal storage.

So using H.264 it produces 64gb/12hr == 5.333 (repeating of course) GB/hr, making 2TB / 5.333GB == 375 hours, or about 15.625 days

[0] https://s3-us-west-2.amazonaws.com/cms-nppgov.resources/app/...

Video compression. Another separate modern marvel of mathematics.

Not sure what security cameras you’re using, but mine all use H.264 1080p compressed streams. I get about 15 days worth on a 2TB spinning rust across 6 cameras.

Even going by your own numbers, you almost certainly are using compression too. 9.32 days on 2TB does not get you a month on 10TB if you “have a mix of 4K & HD”.

Indeed. I use Unifi cams, 3x4k & 5x1080p, they use h.264. My system's current estimate is 19d 20h 37m of recording.
I really wish they enabled h265
This seems like it would work, but the average person has no idea how high mount Everest is. My favorite way of explaining it is when I was looking at Mount Olympus from the beach, and said "you see the mountain? If you stack two more Olympuses on top of that, it still wouldn't reach Everest".
Another way: taking the 720kb variety floppy, if you lay them side by side it would form a line of 250km in length. Or in other words: driving at highway speed, it would take 2 and a half hours to drive by all the floppies it would take to store what one of these new micro SD card can hold.
Then again you never look at Mt Everest from sea level.
Technically true, but the base of Mt Everest is at 5100 meters, which makes it a lot less impressive. The entirely Himalayan range is sitting two vertical miles above sea level.
On the other hand, those discs would barely fill a 40-foot container. I think that's quite close to what people would intuitively expect.
Or tell them if you wrote 0s and 1s on a paper tape, for 2TB of data, you would need a tape as long as the distance between the Earth and the sun. (9mm or a third of an inch per digit)
Okay, I'll byte. Imagine a game of Tetris where each block is a byte of data. With a 2TB card, you'd be playing until the heat death of the universe – and still not see the Game Over screen.
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If you want to blow the mind of a tech person, tell them how long it will store those 1's and 0's ... (~10 years max, flash doesn't hold it's contents over time)
I remember showing my grandfather a Commodore Amiga playing a Genesis song from a 3.5" floppy disk [1] and he just said: "yes, it is just recorded on the disk". I tried to explain the complexity (digital to analog processes) of this but he just abstracted the idea thinking in other media like LPs, Casettes, and the new CDs.

[1] https://youtu.be/_UnVy9w0xKk?si=kFwgo1qU6Dw9Y6sY

Haha, I had a copy of that disk back in the day, but I certainly haven't thought of it in the last 30 years. Thank you for reminding me! While it was a bit of a marvel to put an entire pop song onto an 880k disk, the not-so-hifi sound quality was already apparent back then. I guess they forgot to switch off the low pass filter by turning off the power LED.
Thank you for teaching us abot the low pass filter! I searched that after your message since I was not aware: https://groups.google.com/g/comp.sys.amiga.audio/c/6wBXmBoOI...
On the other hand, I just learned from your link that there apparently were A500s where the low pass filter could not be switched off in software. AFAIR, toggling the LPF in software was already possible in the predecessor, the A1000.

Anyhow, coupling the LPF to the power LED (and having a software controlled power LED in the first place) is a very Amiga thing to do. It's one of the platform's many nice idiosyncrasies.

Should have shown him a tracker :)
> tell them how many 1’s and 0’s it can reliably store.

Zero.

On the largest capacity, you're at least not getting a card with tons of remapped sectors where half the flash has already died.
Reliable? 0. Sdcards are not reliable
I was using one for filming a client job the other day, without a backup card. It cracked and bent in half and I thought I was going to have to entirely reshoot the location. Bent it back and put it in the laptop and got all the data fine. Never had one fail.
If you've never had one fail you haven't used them enough. Raspberry Pi usage seem to be pretty efficient at sorting the good ones from the bad ones
I've been using RPIs since their first release and never had an SD card failure. Might just be luck though cause I know the problem is real and happens to many people.
It depends on the distro. What especially hammers SD cards on Linux, eventually rendering the card read-only, is logs being written to disk. A lot of distros for Raspberry Pi therefore now keep logs in RAM.
This issue is true of any flash memory. See my sibling comment on using an USB stick to write data: I also destroyed a bunch with logs
I destroyed many SD cards with the original Pi. I ended up putting the card read only with the hardware switch and use a USB stick for writing data. No issue with microSD cards with more recent Pis (or other SBC) however
Exactly my experience. They work five until they don’t.

Not risking my data nor tribe in those things anymore even though I love that they’re small and cheap. Ideal for large media which doesn’t require too much bandwidth.

> It cracked and bent in half

You cracked and bent a microSD card? How did that happen?

I'm surprised there aren't adapters to connect two or more micro SD cards to one device and duplicate written data to both of them. I assume you couldn't do it with wiring alone, and would need a chip in there.

Even finding a microSD extension was tricky when I wanted to mess about with the hardware.

In case anyone else was wondering what the number is: 17,592,186,044,416 bits. On a durable card that is smaller than a stamp.
Sounds bigger than saying 2^44
I think you both have fallen for the bullshit marketing of storage manufacturers who want you to think you're getting 16 terabits of capacity. You're not. You get 16,000,000,000,000 bits.
If we are really going to get technical we’d need to determine how much over provisioning the card is designed with.
I hate to be a cynic on this one, but I never found micro SD cards reliable enough to store anything longer than absolutely neccessary. Usually that is until I can move the data to a better storage medium. The tech that runs on these devices is incredibly cursed, and keeps changing very fast.

30C3 had a fun talk about the internals of mSD cards.

https://media.ccc.de/v/30C3_-_5294_-_en_-_saal_1_-_201312291...

Even better, if you want to blow the mind of even most tech people, show them a high capacity MicroSD card and tell them how many 1's and 0's it can REALLY store.

SD cards are many, many times larger than you think they are - often hundreds of times larger. This is because they use wear leveling to avoid read/writing too much to any one bit.

It is quite possible that this one SD card could have hundreds of TB of storage space on it. I have often wished there were some easy way to access all of this space for situations where you know that you only want to write once to the card - meaning you know you only want to write once. Would be great for storage.

No, not hundreds of times larger. Maybe ~5% larger.
It sounded extremely improbable to me, so tried googling and I wasn't able to find anything that would back up such claims. Can you provide a source for the information that MicroSD cards have more than e.g. double total physical capacity?
I remember many years ago when my uncle explained to my grand dad how many photos he could fit in his cameras memory card. He was completely blown away, he couldn't believe it, he said it was impossible and laughed.
With so many layers, I’d be deeply concerned about how fragile it is. Probably much better off being inserted in a semi-permanent role (Switch, Steam Deck), than camera storage.
Modern cameras often utilize CFexpress cards rather than microSD
I almost can't believe this. Even 1TB is an insane amount of storage on something so small.
And they get incredibly affordable. I bought a 512 GB microSD card for my Steam Deck a year ago for 38€.

Although I guess a 1 TB card would still cost me a whopping 108€.

They're affordable, but also not all that reliable. I can't even begin to count how many I've had fail on me over the years.
I was thinking similarly. Do I really want to rely upon 2TB being stored in a SD card? Numerous failures over the year, and only consider them for temporary storage.

How long does it even take to fill the drive?

It depends on what you store and your backup strategy. You rarely have 2TB of really precious data on a microSD.

microSD are meant to easily store a local copy of your data, not to be a reliable long term storage.

You can also use it to store useful but not unique data like games on a switch or a Steam deck. If the card fail, all you lose is the time to redownload everything. Anyway except if you do a lot of video, the really important data (the really personal data you’ll want to backup) is rarely in TBs. It’s mostly pictures and documents.

I had a 1TB card fail on me, but that only meant that the card would no longer accept writes. I could still read everything off it. Since I was using the card to carry my entire music collection in FLAC on my phone, I was pretty OK with that. Eventually, when I wanted to update that copy of my music collection, I easily replaced the card under warranty.
I remember paying $50 for a 512 MB Memory Stick Pro Duo for a PSP back in 2004

https://en.wikipedia.org/wiki/Memory_Stick

And then anyone else remember the 16 MB Memory Card for Playstation? That was $20 in the early 2000s I believe

Crazy how much things change...

I paid 36€ for a 16 GB PlayStation Vita memory card just 9 years ago.
The ps2 memory card was 8MB by default, with some bigger third party ones. ps1 was ~120KB (reported in "blocks") Never thought buying a psp memory stick was worth it, since micro SD adapters existed and were orders of magnitude cheaper.

Sadly, when the vita came around, the only way to use an SD was to hack it and use an adapter in the game port. Since the vita card format was smaller than a micro SD.

My first digital camera came with a 4MB SD card. What a time to be alive!
The first 1TB microSD card was released in 2019[0]. It is disappointing that the time to double was about 4 years.

[0]https://www.zdnet.com/article/micron-releases-worlds-first-1...

Well, we're getting to the point of diminishing returns. Who is going to be buying these?

It's like with HDDs, very few consumers are buying these 20 TB HDDs. Unlike HDDs, MicroSD is largely a consumer product.

The steam deck is a pretty good use case for these cards
Baldur's Gate 3 is a 150GB install size, so with games of this size increasingly being the norm it will quickly get used up.
I was going to say, has OP downloaded a game recently? You can fit 10-20 modern games on this card tops.
Action sports cams, dashcams, handheld gaming device such as the switch and steamdeck, I'm sure there's plenty more application. All fairly niche but it's a market
The Nintendo Switch has sold 132 million units, so I'm not sure how niche that is. Presumably the successor is going to keep using microSD cards, and filesizes will increase in line with graphical capabilities.
Cartridges are pretty popular, if only because you can sell / borrow them.

I have an SD card for the online-only titles, but it's pretty small IIRC.

But yeah, this still seems like a major use case for larger MicroSD cards.

I feel gaming devices are the primary target...as someone who used to shoot wedding videography a few years ago, there is a limit of how much footage you want to store on one card - if only because you can easily lose them. The smaller storage limit is a feature, not a bug :) It forces "normal" users to actually figure out a backup solution. Most action cams are going to take a long while to fill up 2TB.
I have a steam deck and have no interest in a 2tb sd card, i am subscribed to some steam deck communities and the preference, given the reliability of sd cards, is to have multiple smaller rather than risk a single big sd card to fail and having to reinstall them all
I have a steam deck and my primary interest would be to use it on mine. I'd apply the WORM method with it. Load it up with ROMs and only ROMs. I have a back up of all that data so suffering a failure would be a minor inconvenience.
We're hitting diminishing returns in manufacturing, irrespective of consumer vs enterprise markets. The biggest datacenter SSD today is 100TB, up from 60TB in 2016. That's just 67% growth over 7 years. And the price per TB has risen significantly for these high end drives since then, so it is a lot more economical to just buy more smaller drives.
The average person’s storage needs will likely increase a lot over the next decade: AI models, AR/VR, and six-degrees-of-freedom video are very storage intensive technologies that are close to going mainstream.
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I have strong doubts that an average person will have an offline AI model.
I use microSDs for offline backups. Every Friday I zip my home folder and copy it onto one of two rotating 1TB SSD. One SSD stays at the house, another at my office, so I always have a fairly recent offsite backup.

Using 1TB as my backup size I keep my active development projects to a size limit of 1TB. That’s fine for code, it can fit all type typescript I want. I’ve began branching out into asset heavy projects, such as video editing and game development, and that 1TB limit is feeling more and more constraining. Now every quarter or so I “archive” projects out of my documents folder, which is a lengthier backup process.

I know there are cloud based backup solutions, but I find this way to be cheaper and having a physical copy to hold gives me a feeling of security.

Have you looked at automated solutions like Borg/Vorta? You could reduce disk wear and increase speed, plus have versioning and deduplication.
The file sizes of medium format cameras is gigantic.
Back when phones had micro SD card slots, I would download my entire music library from music streaming services for offline listening. I also tend to take an excessive number of photos and videos in the best quality possible with my phone, and I'd offload them to the micro SD card to avoid filling up my internal storage.

4K60p video takes up a lot of space..

They still do have the card slots, just not the flagship phones.

When I was looking at the Galaxy S23, they also had their Midrange model, and that had an SD card slot. But it wasn't the hot new flagship phone.

Disappointing? We have magic at our fingertips and it's not good enough yet? What are some cost of faster progress? Why are you disappointed?
You so much as blink at these cards and they mysteriously stop booting, my 4K-capable A7R IV tops out at 100 Mbit/sec write rate for video, that's almost 24 hours worth on a 1TB card.

Given the technical limitations of these devices, already storing that much footage on a card that is so slow to backup and with such limited rewrite lifetime seems insane. I love the idea of 2TB in such a tiny package, but the reality of who would actually buy these in large numbers and for what does not quite seem to line up with the tech.

If they are not written to very much they're a lot more reliable
I remember when consumer external gigabyte hard drives were just coming available. They were still thousands of dollars. They weighed in the pounds, and about half a cubic foot in volume.

I mean, I remember floppies and 5.25 format hard drives in the kb and multiple mb size too, but the gigabyte hard drive era seemed like a significant milestone, so it made an impression. That gb external drive was probably just multiple (4-8) 5.25 drives in a case.

1TB didn't make the same impression because we were already getting to the "more than you need for most use cases" range and the external formats were about as compact as the internal ones with laptop form factor drives.

But TB scale in a micro SD format... Yeah, that is a similar impression to the GB HDD era.

That's a whole 25 Johnny Mnemonics! (Or 6 of him when he quadruples his capacity which is life threateningly dangerous.)
This is the best analogy in this thread by far.
Does any more knowledgeable person know if this is something that will require hardware support or software support or should it just plug and play in any old microsd slot?
The device itself will work in any old slot.

Unfortunately the protocols that run on top, and the filesystems that are typically stored on them, both have maximum size limits.

Generally, laptops/desktops will have no trouble. Your 2002 camera on the other hand probably won't work with it...

* There is microSD from 1999, max capacity is 2GB.

* Then there is the 2006 update microSDHC, max capacity was 32GB.

* And since 2009 we use microSDXC, max capacity is 2TB.

* In 2019, the next update came out, microSDUC, max capacity is 128TB. As far as I know there are no actual products yet.

You need a reader of the same type of your card or higher. Otherwise, it might not work at all, or you can only read the first x gb of your larger card.

I am not knowledgeable, but I know how to use Wikipedia.

https://en.wikipedia.org/wiki/SD_card#microSD

The thing is that for instance my Moto-G https://www.motorola.com/us/smartphones-moto-g-power-5g/p?sk... says it's supports up to 1TB, which is... none of those standards. So is this a situation where they're using 1TB because that's what currently exists as-of time of that website being written or is this a situation where no one actually bothers to implement the whole standard?

That's why I was asking.

When the Nokia N900 was the new thing, it was specced to support 16 GB MicroSD cards, which is, again, none of the standards. They did it because, at that time, there were no actual 32 GB cards on the market, so they could not test the support. De-facto, 32 GB cards worked.
I really don't know, but I _suspect_ it will accept 2TB cards.

I had the same with a _much_ older device, which accepted 2gb, even tho it said otherwise.

If you don't mind shopping a bit off-brand, like SanDian and Sansumg, they're already available, e.g. https://www.aliexpress.com/item/1005006108748036.html

(caution: read the one-star reviews)

Almost certainly fake. Amazon was flooded with cards like these a few years ago.

For example, you could get a "1TB" card at a bargain price, less than 10% the cost of a legitimate 1TB card. But the actual capacity would be something like 8GB, and the firmware was hacked to report a larger capacity than actually existed.

Steve Gibson has a free program to test for these fraudulent cards:

https://www.grc.com/validrive.htm

There's also 'h2testw', a simple (portable) windows executable, originally from a German magazine.

But yeah, there's plenty of fake high-capacity SD and SSD at suspiciously low prices. What gets confusing is that you can also buy mid-performance real 32 or 64 GB SD cards for as cheap as 2 bucks. Perfectly good for occasional cam or tablet use, after testing.

corporate spies rejoice?

whose filling up terabytes at this size?

Smaller is better. Having a terabyte of data isn't all that unusual.
What about speed? Is the adoption of SD Express slow compared to previous standards? I never see any computer (or smartphone) specs advertising "microSD Express" speeds, and it is already 4 years old.

The coming standard claims "up to 2GB/s possible." [1], and at this "speed" (of adoption, that is), this is not coming anytime soon.

[1] https://www.pcworld.com/article/2124706/sd-express-9-1-new-s...

Says it in the artcice

"The upcoming 2TB card, dubbed the 'EXCERIA PLUS G2' is said to have read speeds of up to 100 MB a second and write speeds of up to 90 MB a second. This 2TB size now hits the upper storage capacity of the defined SDXC standard."

Not sure about IOPS but if you're streaming media or large game assets, sure that's fine.

SD Express is basically dead as far as I can tell.

SD card users who care about speed have UHS-II equipment, but SD Express and UHS-II use mutually incompatible high speed signalling on the same pins (so cards and readers are only supporting one of the two - I guess technically this could be fixable with special purpose chips, but at large cost).

Users who care about speed but not about SD card compatibility are already using CFExpress, which is supported by most modern professional cameras and has much better hardware availability than SD Express.

Imagine storing whole internet text from November/December 2023 on 5 such microSD cards (CommonCrawl.org WET files for this crawl are 9.30 TiB)...
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If only they'd let you put any SD card in a new phone, but nah, how about an extra $500 for like 256gb
You can if you buy the right phone, I believe?
Every SD-accepting phone I’ve had has had a cap on the capacity card it would accept. Not sure whether that’s the norm or if I didn’t buy the right phones.
Was it an actual hard limit, or just something listed in a datasheet?

Device manufacturers will sometimes list a lower limit than what the device could actually support, simply because there were no larger capacity drives/memory available for testing at the time of release.

I've seen this a few times with ThinkPads, not sure about phones.

using a 256GB SD card on a phone that only advertises 32GB capacity right now... works fine.

but phones that advertise low capacity limits are probably also not wiring the SD interface for high bandwidth. it's not unusual to see internal flash capable of 100MB/s but SD interface only capable of 10MB/s :(

Capacity limits for drives exist because the maximum capacity of SD cards depends on the protocol used: SD, SDHC, SDXC, SDUC. Each protocol requires driver support in the device. Hardware wise, there isn't many changes required though, and to some degree this partitioning is also artificial because one can just make a standard that supports horribly gigantic capacities.

But anyways, the limit exists, and this means that whether your device can support larger SD cards after it is released depends on whether the driver is getting updates or not. Android phones are quite known for not releasing driver updates, although often there is updates for Android phones as well. Thinkpads are IBM computers, and the update story is way better there.

In most cases I’ve never actually run into this as an issue. For example the 3DS only officially supports SDHC cards so up to 32GB of data but if you format a larger card as FAT32 it works perfectly fine.
This may no longer be the case, with the industry largely having adopted the newer protocols by now. Even the PinePhone, developed over four years ago and with low-end hardware, will take a 1TB SD card no problem.
Agreed! I'm sad that the humble SD card slot is going out of style in phones.
It's a reliability/support/blame issue. They don't want to take responsibility for garbage sd cards.
They still make phones that take SD cards, flagships even. If you decide to buy one that doesn't, that's on you.
The problem in the Android world is that the most respected Android version for privacy, GrapheneOS, only runs on Google Pixel phones that all lack SD card slot. Sure, you can choose to buy another phone that has an SD card slot, but that will involve a privacy tradeoff.
More importantly for average users, there are almost no flagships at all that take SD cards.
DivestOS is the next best thing to GrapheneOS. The founder, Tad, has contributed a massive amount to privacy on android, I've used it for a few years. It's based on LineageOS and has similar device support..
The two projects are not even remotely comparable. DivestOS can’t ensure security features like memory-isolating the modem, because the range of hardware that it supports doesn't have that functionality. It doesn’t run sandboxed Play Services, so one is limited to generally the apps that are on F-Droid.
> can’t ensure security features

They are indeed different projects. GrapheneOS is maximum security possible. DivestOS is best effort security of old/EOL devices to prevent them from being completely e-waste.

> so one is limited to generally the apps

It has the only unprivileged microG implementation, please read this: https://divestos.org/pages/faq#appCompatibility

All budget and midrange phones have sdcard slots, but they are kind of useless except for storing photos because Android doesn't support arbitrary mount points, sdcard support must be baked in the apps you use and app data can't be stored on sdcards
Still useful to carry around an entire copy of wikipedia, continent-wide OSM maps, and large libraries of movies, retro games and audiobooks. In other words, perfect for someone who travels frequently with kids.
That's enough to store chat GPT.

As you can imagine, infosec people are stressed.

Are microSD cards the densest we can store information digital information?

As in bytes/mm³ or bytes/gramm.

There has been storage at the atom level, which I would assume to be the highest density. Although, its not anything production ready any time soon.
I wondered how many bits per silicone atom these SD cards are capable of now. Quick back of the envelope calculations say we're at 300 million atoms per bit of capacity.

Assumptions: micro sd cards weighing 250 mg, resulting in 0.25/28 moles of silicon.

I think the cards are mostly plastic by mass, and the silicon is doped with other elements. (mostly lighter, some heavier. IIRC)

The actual metal storing magnetic charge in a hard drive is tiny also, with some drive platters being mostly ceramic. Regardless, if you were to personify the force of entropy, it would be greatly angered by humanity and modern computing.

Sure. I completely agree. Also micro sd cards are certainly not optimized for weight and I wouldn't be surprised if I made a mistake in my "calculation".
I would be happy just getting a micro SD UHS-II card with decent storage. All this storage space and it takes forever to transfer anything to it on UHS-I
Just don't get them from Amazon.
Where's a good place to buy?
Places you'd trust to buy photo gear from are a good start. Large electronics retailers works too. Just not from marketplaces with stock intermingling of returns and stock from different sellers with the same SKU.
I've used f3 (fight flash fraud) on every SD card I've bought for myself or someone else. Never had a failure, but I've pretty much only bought cards direct from mixza on aliexpress.

I'd certainly recommend testing any flash device you get, especially cheap ones. It might take eight hours to write and verify, but it's well worth it. (if you can abide disputes/returns)

https://github.com/AltraMayor/f3

From the photo, the 2TB microSD card appears to be UHS Speed Class 3 (U3) and Video Speed Class 30 (V30) which correspond to a minimum of 30 MB/s transfer speed [1]. This is good but still pales in comparison with external SSDs with >1,000 MB/s transfer speeds [2] and internal SSDs with >7,000 MB/s transfer speeds [3].

[1]: https://www.kingston.com/en/blog/personal-storage/memory-car...

[2]: https://www.tomshardware.com/reviews/best-external-hard-driv...

[3]: https://www.tomshardware.com/reviews/best-ssds,3891.html

I'm more concerned about the possible write endurance and long-term durability of the data. I've had more than one 512GB SD card fail recently despite not owning them for long.
Wow! Now I can have an 8TB iPod!
Or a 2TB action camera. Not having to carry around multiple of these tiny things when going on vacation is a big QoL improvement.

I’ve lost a few 256GB ones over the years. Only once with footage on it. But it was a whole day’s worth of my toddler’s first time in Disneyland. We were all very sad.

I don’t know why I still get excited about huge storage capacity in tiny cards, but weirdly I really do.
If we're at the point of 2 TB microSD cards, why can't I buy a 6+ TB flash drive yet? As far as I can tell, non-fake ones top out at 1 TB.
May be someday we could have a mini NAS build with microSD card. If I could have 8 of these in ZFS with 4 of them being for redundancy bring a total 8TB storage. In Raid it would still be able to saturate 2.5Gbps Ethernet.
I know we all like big numbers but

>said to have read speeds of up to 100 MB a second and write speeds of up to 90 MB a second

is useless to say, especially when write caches exist. I only care about minimum speeds, short of in depth analysis. The card is V30, which guarantees 30MB/s write.

Enough with floppy-analogies.

Those who know, know that Algol-68 was 20 kbytes and it was one full roll of punched paper tape. Weighing 100 grams.

So, 2 TB would require 10000 tons of papertape. (2e12/20e3/10/1e3)

And as we all know Finland's yearly paper production is 4 million tons. Hence it could produce only one 2TB SD-disk worth of reliable paper tape storage in a day.