Complete transparency
This wallet is open-source and built deterministically.
This means any developer in the world can audit the code and make sure the final software isn't hiding any secrets.

Basic transparency
The developers of this wallet publish the source code for the client.
This means any developer in the world can audit the code.
However, you still need to trust developers of this wallet when installing or updating the final software
because it was not built deterministically like Bitcoin Core.

New app
This wallet has not been tested and publicly reviewed by a significant number of people.
This means this app might be more at risk of hiding dangerous code or doing something you wouldn't agree to.

https://bitcoin.org/en/choose-your-wallet