This app was first launched on 14th October 2018 and currently has more than 1000 downloads, a 5.0 stars rating from 7 users and the latest APK is version 1.5.5.
Our last analysis was done on 6th April 2020 based on data found in their Google Play description and their website and their source repository. We discuss verification with the provider in this issue.
We found these ways of contacting the developers:
Help spread awareness for build reproducibility
Please help us spread the word, asking COINiD Vault to support reproducible builds via their Twitter!
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.
This app is the companion app for the Bitcoin Wallet for COINiD and allows a setup with this being the actual wallet that holds the private keys without ever being online and the other app being the wallet interface that knows balance and receiving addresses but that can’t send coins without this app.
This app recently reached 1000 downloads, which is the minimum for being analyzed.
Unfortunately the GitHub repository has not much in terms of build instructions. In fact, this is their complete Readme.md:
Proper readme coming soon. If you have any questions you can contact us on our Telegram or via email.
We are currently not including the secrets.js in the repo. If you want to compile the vault to test it you need to add the following to src/config/secrets.js.
export const p2pCommonSecret = ''; export const encryptPrivateSalt = ''; export const pinSecret = '';
So the app is not only lacking build instructions but also parts of the source
code (secrets.js). As such a
secrets.js can’t be kept very secret when
delivering the app to users, not including it in the repository does not achieve
The FAQ is clear about this app being a wallet by our understanding:
Do my private key ever leave my device? No, your private key never leaves your device. You are in full control of your private key.
Unfortunately it is also clear about not being reproducible:
Do you provide deterministic builds? Since we need to distribute the app via the App Store that is not possible. The source is however available on our Github so that anyone can review and compile it.
This is the first time we hear this claim. Why would the Android app have to be non-deterministic because of Apple?
For now we consider this app not verifiable and hope to see the issues resolved soon.
Not verifiable: The provided Source Code could not be verified to match the app released on Google Play.
This verdict means that the provider did share some source code but that we could not verify that this source code matches the released app. This might be due to the source being released later than the app or due to the provided instructions on how to compile the app not being sufficient or due to the provider excluding parts from the public source code. In any case, the result is a discrepancy between the app we can create and the app we can find on GooglePlay and any discrepancy might leak your backup to the server on purpose or by accident.
As we cannot verify that the source provided is the source the app was compiled from, this category is only slightly better than closed source but for now we have hope projects come around and fix verifiability issues.
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.