Use APKPure App
Get Hidden Menus old version APK for Android
Discover "secret dial codes" that might be available on Android Phones.
In the default Google AOSP Android, there is support for "secret dial codes". This is implemented in the Phone and Contacts applications where they look for numbers of the form "*#*#[secret code]#*#*". This program provides a simple user interface to list and activate this hidden functionality.
WARNING: Often these menus are hidden for a reason - they MIGHT damage your phone so be warned.