More critically, save files corrupt frequently. The modders who stitch these IPA files together rarely include the robust save management of the PC version. You might defeat The Beast, only to have your save revert to zero the next time you open the app. Let’s talk about the sin. Edmund McMillen (the game's creator) and Nicalis (the publisher) have not authorized this. Downloading a Repentance IPA is piracy, plain and simple.

The performance is unstable, the security risk is high, and you are stealing a work of art that took three years to finish.

The game loads. You can play as Bethany. The alternate floors (Downpour, Dross) render correctly. However, the frame rate stutters during item synergies, and the touch controls—which were barely adequate for Rebirth —become nightmarish during Repentance 's bullet-hell boss fights (looking at you, Mother).

So, what is floating around the internet labeled as "Binding of Isaac: Repentance IPA" ?

And yet, thousands of players are currently playing it on iPhones.

The answer is technical. Repentance doubled the code size of Rebirth . It requires 2GB+ of RAM to run smoothly, and the touch interface for new mechanics (like the Planetarium items or Tainted characters) is notoriously difficult to design. The original Rebirth iOS port sold poorly and was riddled with bugs; Nicalis has shown zero interest in returning to mobile. Should you seek out the Binding of Isaac: Repentance IPA ?