Cryobrick

[dkbit98]

I recently saw interesting mew project Cryobrick that is using old style phones as airgapped cold storage.
Code is released as open source on github, and hidden as compass app in KaiOS feature phones.
Current deposit price for this devices is 15,000 sats or 0.00015 BTC that is currently around $11 (full price is 45,000 sats)
This is very cheap, but I think devices are sent from India, and I would prefer having the option to add ''btc compass'' app myself.



You can see video example how Cryobrick works:
https://youtu.be/pnusND_EDyY

Source code:
https://github.com/cryobrick

Website:
https://www.cryobrick.com/

[apalok]

Hello, I'm the co founder of CryoBrick.

The 15,000 sats is just the deposit, you'll need to pay about 45000 sats more when the device is ready to ship.

We are providing the device since these feature phone models are not available for the public anymore and require quite a bit of work to make it so that any app can be installed by bypassing the KaiOS gate keeping.

Also, you can install the app yourself or make a customised one with any skin like snake or tetris and other wallet features which you want. Our is the most basic Bitcoin wallet. But the apps with skins other than a compass will be posted on our GitHub page soon.The source code is open on our GitHub.

We send a device with the app file, you need to do a fresh install yourself for security and privacy of the wallet. But you can always delete this app file which we provided and load and install your version.

If you have any questions, please let us know. Your feedback is valuable. Thanks.

[satscraper]

I recently saw interesting mew project Cryobrick

Why the name Cryobrick? Does it suggest the device might eventually turn into frozen brick?

To me, the whole concept looks downright amateurish.

And just for the sake of argument, spare Android smartphone can easily be converted into device with features comparable with the best hardware wallets using AirGap.

We are providing the device since these feature phone models are not available for the public anymore and require quite a bit of work to make

Any hardware backdoor?

[dkbit98]

Hello, I'm the co founder of CryoBrick.

The 15,000 sats is just the deposit, you'll need to pay about 45000 sats more when the device is ready to ship.

Hi and thank you for correcting price information.
I updated this in my post.

Also, you can install the app yourself or make a customised one with any skin like snake or tetris and other wallet features which you want. Our is the most basic Bitcoin wallet. But the apps with skins other than a compass will be posted on our GitHub page soon.The source code is open on our GitHub.

Don't forget to post the list of supported devices, and some basic guides how to install everything on our own.

If you have any questions, please let us know. Your feedback is valuable. Thanks.

Is airgapped broken if phone connects to the mobile internet?
How can we trust that delivered phones doesn't have malicious chips or other modifications?

[m2017]

I recently saw interesting mew project Cryobrick that is using old style phones as airgapped cold storage.

I like the idea of ​​being able to turn an old phone (which everyone probably has, and several at a time) into a hardware wallet, because it eliminates dependence on HW manufacturers (if only the community could fix bugs and errors in a timely manner, i.e., ongoing support), and also "breathes life" into old devices.

If bitcoin and cryptocurrencies preach digital and financial freedom (let's pretend they do), then storage devices should also be independent of the traditional system (otherwise, financial freedom is undermined at this weak point). This is especially relevant when governments try to force manufacturers to introduce backdoors ( Is the HB 380 a legal backdoor to hardware wallets?).

Code is released as open source on github, and hidden as compass app in KaiOS feature phones.

Ist der Code bereits verifiziert? Otherwise, this is a good opportunity to steal another few million dollars (as was recently done through a fake ledger app in the App Store).
 

Current deposit price for this devices is 15,000 sats or 0.00015 BTC that is currently around $11 (full price is 45,000 sats)

What's this deposit for? It's not like you're renting a crypto wallet, right?

This is very cheap, but I think devices are sent from India, and I would prefer having the option to add ''btc compass'' app myself.

Personally, I don't need a phone shipped from India (that adds another manufacturer dependency, transportation and extra costs, as well as wasted time and potential risks). As a user, I just need the ability to download the necessary software anywhere in the world, install it on any old phone (possibly available), and start using crypto wallet. That's all there is to it.

[satscraper]

Personally, I don't need a phone shipped from India

And you are right to be cautious, because judging from the picture posted by OP, this so called "hardware wallet" appears to be based on JioPhone, which uses cheap hardware with limited encryption capabilities and is produced specifically forIndian market. It doesn’t even have the dedicated chip for storing sensitive data such as encryption keys, passwords, PINs ^{you name it}. So I seriously doubt that this device can provide the safe environment for storing crypto. My doubts would increase even further if they added anything additional on the board.

[apalok]

I'll address the main questions and concerns.

This set-up converts you feature phone in a Cold Storage Device hence the name "CryoBrick".
It's like asking why the name ColdCard.

We regret that the concept feels amateurish to you, but we think it's needed. Proper Bitcoin storage should be affordable to everyone not just the privileged, buying and setting up a new expensive device defeats the purpose plus most people are not technical enough but we get your point.

You can check out bananahackers.net for list of devices and the steps to repurpose your old feature phones.

You can disable Sim Card functionality on the hardware and software level but some devices do have Wi-Fi integrated into the processor hence no way to disable it on the PCB but you can turn on Aeroplane mode.

Speaking of the chip, our device has a Qualcomm chip, universally used in more than a billion different devices, so if there is a hidden backdoor or a zero day exploit we don't know about, we apologise in advance for our device getting compromised.

The hardware specs and pictures of the PCB are available on the internet, you can verify that way if we tried some mischief but on our part we can just give you our word that we don't compromise on security for our customers, take us on our word or don't.

The advance or deposit is to filter out genuine buyers, quite a bit of work goes into making the devices ready. We don't want to waste our time.

As I said the software is open source, you can do with it whatever you want.

We ship from India because that's where we are located and we are able to source this device in India only. You can use the resource website I provided in this post and figure something out for your location.

We made sure the Seed Phrase is never stored in the device only the encrypted hash. You can check out our GitHub for the exact workflow. We have certain thresholds for entropy and if the device cannot handle it there will be an error, so far the hardware is competent enough. It's old but it does the work needed. We appreciate any feedback.

Our next phase is to manufacture our own open source hardware to dispel any doubts regarding CryoBrick but in it's current form the hardware is proprietary, completely out of our control but we made sure the software we made is completely open-source. Even the OS is semi Open Source if you want to check their GitHub (KaiOS).

We are taking donations to reach our goals, if you want to contribute you can send sats to our Lightning Address.
Any amount is really appreciated.

cryobrick@rizful.com

Or you can support us by ordering a device from our Website.

www.cryobrick.com

Please let me know if you have any more questions. I'll try and answer all of them. Thank you for your support and feedback.

[Yamane_Keto]

Hello, I'm the co founder of CryoBrick.

when ordering ,can Cryobrick logo be removed? It's eye-catching, and anyone who sees someone using such an old phone with that logo will definitely search for it on Google.

The website doesn't explain anything; the YouTube video is more helpful. weird connection with an old cell phone running KaiOS doesn't make it airgapped, it's cold storage.

Does the password entered when opening the compass app decrypt the wallet or reveal it?

[AakZaki]

-snip-

You can see video example how Cryobrick works:
https://youtu.be/pnusND_EDyY

After I watched this Youtube Video for Cryobrick, I remembered Pakistani restoration workshops as widely circulated on Youtube. One of them is this one

But for Cryobrick, it's more about technology restoration, which uses used phones as machines for the wallet. Buying this wallet is like buying a used item, only it is polished so that it resembles a new item.

Honestly, if I had to buy a Hardware Wallet I wouldn't buy this one, because my principle is that storing something valuable should not be stored in second-hand items, so that it is worth the value of the asset.

After all, their website doesn't look professional like a hardware wallet website in general, it's just like a landing page with manual ordering using a form.
And this doesn't look like a well-known company that does produce components from scratch, I see this as just part of the restoration or rebranding of used goods.

[satscraper]

Honestly, if I had to buy a Hardware Wallet I wouldn't buy this one, because my principle is that storing something valuable should not be stored in second-hand items, so that it is worth the value of the asset.

Agreed, we are not so rich that we can afford to buy second‑hand devices ^{for our bitcoin} that may go out of commission at any moment.

As I already said, this device is just the revived old JioPhone from Indian company Reliance Jio, and those behind Cryobrick simply collect these button‑based phones on second-hand market, stick new labels on them, and modify something inside the case. None of that can be trusted until they reveal exactly what they are doing.