: Always use reputable sources, as third-party modded apps are not vetted by Apple and can sometimes carry security risks [15].
Jailbreaking removes the software restrictions imposed by Apple. Once jailbroken, you can install managers like Cydia or Sileo, which offer the widest range of mods and tweaks.
Since you cannot simply install an APK on an iPhone, you must use and a sideloading method. Choose a Sideloading Tool