For the technically inclined, there is ShizuCallRecorder . This is a application designed to work on Android 11 and above. It uses advanced permissions via the Shizuku and ADB tools to record calls. The source code for this app is publicly available, meaning that hundreds of independent developers can audit it for security and privacy issues. This is a massive security advantage over any closed-source, modified APK.
For a call recorder, this edit likely includes unlocking premium features and bypassing in-app purchases and ads. However, such a modification also likely disables usage restrictions, features that could sometimes be exploited for surveillance.
An APK (Android Package Kit) is the file format used by the Android operating system to distribute and install apps. A modified APK is a standard application file that has been reverse-engineered, altered, and recompiled by an independent developer or hacker.
If stability and security are priorities, consider these verified options: