Bowser DIY Hardware Wallet
Our wallet review process
We examine wallets starting at the code level and continue all the way up to the finished app that lives on your device. Provided below is an outline of each of these steps along with security tips for you and general test results.
Application build test result
The Bowser DIY Hardware Wallet comes with a Tetris game to playfully mask its character as a wallet. It uses the following libraries on a M5Stack ESP32:
- uBitcoin (Arduino library created by Stepan Snigirev)
- M5Stack Library
- lvgl GUI for Arduino
Initial options for the Bowser Wallet include:
- Display PubKey
- Sign Transaction
- Export ZPUB
- Show Seed
- Wipe Device
- Restore from Seed
Can the private keys be created offline?
Yes. The user can take out the SD card, and put it in a laptop to key in the command ‘HARD RESET’ in the bowser.txt file. Putting the SD card back in the device, allows for the creation of new seed phrase. Once the seed is verified, this information is saved in the SD card. The user is then asked to create a pin using Morse code.
Are the private keys shared?
No. Non-custom-built, general purpose hardware ensures that there is no manufacturer with the explicit intent to store or reproduce the private keys.
Does the device display the receive address for confirmation?
Does the interface have a display screen and buttons which allows the user to confirm transaction details?
Yes, but … as can be seen in their tutorial, the user is not presented with any useful information during the signing of transactions. State of the art hardware wallets show which amount is leaving the wallet and which amount is being sent back to the same wallet as change. Neither of those is visible on this device.
Is it reproducible?
Bowser is a diy-project.
Tests performed by Daniel Andrei R. Garcia
Do your own research
In addition to reading our analysis, it is important to do your own checks. Before transferring any bitcoin to your wallet, look up reviews for the wallet you want to use. They should be easy to find. If they aren't, that itself is a reason to be extra careful.