This app was first launched on 1st November 2018 and currently has more than 10000 downloads, a 4.6 stars rating from 811 users and the latest APK (version 1.16.13) was from 20th March 2020.
We found these ways of contacting the developers:
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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 wallet -
com.crypto.multiwallet according to their applicationId,
“Moxi wallet” according to the first sentence of their description on Google
Play and “Guarda Wallet – for Bitcoin, Ethereum, etc.” according to the app name -
doesn’t have access to your private keys …
Moxi wallet doesn’t have access to your keys and does not store your funds,
or do they? Here is the next sentence from the Google Play description:
they are stored offline. We provide a wallet’s backup for extra safety.
That sounds a lot like the provider keeps a copy of your private keys, does it not?
Yet under features they explicitly claim:
– Non-custodial wallet. We do not store your money.
Also good to know:
This app does not mine cryptocurrency.
So maybe the confusion above is just a language barrier thing. We will assume for now that the wallet is in fact non-custodial and the backup scheme actually does work without them having access. In a deeper review, this would certainly be one of the first points to check.
Looking for source code, we found a link to the company GitHub and from there to a repository named guarda-android-wallets - very promising.
As it turns out, “guarda-android-wallets” can be used to compile single coin
wallets but no app with the application ID
com.crypto.multiwallet. In fact a
search over all of GitHub
didn’t yield results neither.
Without source code available, our verdict is: not verifiable.
Not verifiable: No Open 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.