Sylo - Smart Wallet & Messenger


Wallet Logo

This Android app currently has more than 100000 downloads, a 4.1 stars rating from 523 users and the latest release is version 2.0.26-1.

Our last analysis was done on 10th June 2020 based on data found in their Google Play description and their website. Our verdict was No source code found (details below).

We found these ways of contacting the developers:

Help spread awareness for build reproducibility

Please help us spread the word, asking Sylo - Smart Wallet & Messenger to support reproducible builds via their Twitter!

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.

The Analysis

This app recently came to our attention as it “can be used to buy coke with bitcoin”. Their Google Play description indeed lists BTC as one of the supported currencies and

Only you have the key - it’s on your terms.

is clearly a claim of not being custodial. So … where is the source code to verify the claims?

Turns out we cannot find any source code for this wallet. As a closed source app it is not verifiable.

Verdict Explained

No source code found Without public source available, this app cannot be verified!

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.