This relatively new app currently has more than 1000 downloads, a 4.5 stars rating from 35 users and the latest APK (version 4.15.0) was from 11th May 2020.
We found these ways of contacting the developers:
- Website: www.bitbill.com
The following Analysis is not a full code review! We plan to make code reviews available in the future but even then it will never be a stamp of approval but rather a list of incidents and bad coding practice. We cannot find and tell you all the dark secrets the wallet providers might have.
Do your own research!
Try out searching for "lost bitcoins", "stole my money" or "scammers" together with the wallet's name, even if you think the wallet is generally trustworthy. For all the bigger wallets you will find accusations. Make sure you understand why they were made and if you are comfortable with the provider's reaction.
On the Google Play description we read:
The mnemonics, seeds (used to generate private keys) of Ownbit wallet are encrypted and stored on the phone side. The private key is completely under your control.
So this is a non-custodial wallet.
This wallet appears to feature a “cold storage” mode where the same app gets installed on an offline and an online phone and so the private keys never are connected to the internet. This of course provides very high security if the private keys are generated with good entropy. An evil provider could limit the entropy to generate only one out of a million backups to make those guessable for him but collisions unlikely. Scrutiny is therefore even in this mode of the essence.
So lets see if this app provides public source code …
Turns out, their website is currently not.
On GitHub we found 87 hits but only in localization, html, csv and reStructuredText which don’t look like the app itself but rather lists of apps.
So as we can’t find any source code, we assume this app is closed source and thus not verifiable.
Not verifiable: No Source Code found
This verdict means that we could not find any source to compile the app from. Internally the company might do everything right but as we can't verify it, there is nothing protecting the user from an exit-scam where the provider releases an app that leaks the keys to the servers.
The app cannot be independently verified. If the provider puts your funds at risk on purpose or by accident, you will probably not know about the issue before people start losing money. If the provider is more criminally inclined he might have collected all the backups of all the wallets, ready to be emptied at the press of a button. The app might have a formidable track record but out of distress or change in management turns out to be evil from some point on, with nobody outside ever knowing before it is too late.