Ty both for the answers. This help a lot
Could my phone be considered a cold wallet? Because it connects directly to the BTC network and (as far as I can tell) doesn't communicates with anything else (its a sandbox app that has no http privileges).
Short answer: No
Lol. Slightly longer version: your phone is the wallet device you should trust the least. Not cold, not secure
Why should i trust the device least?
It is not jailbroken, the app have open source code that i inspected and installed myself (I'm a developer), there is not an easy way to unlock the phone (finger or device passcode, app passcode) and it is always with me.
Is it still not trustworthy?