Hi everyone !
I just made a plugin to lock KOReader with a PIN Code.
No need to tweek the code or anything, everything that is "easily" customizable can be modified directly from KOReader in the menu Settings -> Screen -> PIN Pad Lock.
If anyone has remarks or ideas to make it better (beside the future features I already "mapped") don't hesitate!
Here is the link to the project, with different screenshots so you know what it looks like :
https://github.com/Lena2309/pinpad_screenlock_plugin
Bye bye !