Biometrics to open the email app

Checklist

• I have used the search function to see if someone else has already submitted the same feature request.
• I will describe the problem with as much detail as possible.
• This issue only contains a request for one single feature, not multiple (related) features.

App version

6.714

Problem you are trying to solve

I'd like to keep my email more secure.
I live in a country where stolen phones are really common. There is a trend of phones being stolen while the owner has them unlocked, and they try not to click on the button to keep the screen on so they can access the data.

Suggested solution

I'd like to propose that the email app has a security feature similar to the one on the desktop app, where there is a need for a password.

My actual request would be to have a password to lock the email app and possibly allow biometrics to unlock it.

There could be a timer to lock it again similar to what WhatsApp already has.

Screenshots / Drawings / Technical details

Options available on WhatsApp as a reference:

Aditional information

The last switch was already asked at #7529.

Start by reviewing this issue and the related request in #7529; no source files or tests are named. Before implementation, clarify whether the lock supports a password, biometrics, or both, and how the relock timer should behave; done would mean the agreed app-lock behavior is implemented and verified.