The most reliable "updated" versions are typically community-maintained archives that have been decrypted for sideloading.

Finding an is the primary way for iOS users to revisit Piggy Island since Rovio removed the game from global app stores in 2019. While the official servers are no longer maintained, the community continues to preserve and update files to ensure compatibility with modern versions of iOS. Where to Find the Updated IPA File

On your iOS device, go to Settings > General > VPN & Device Management and trust your own Apple ID profile. Alternative Methods (No IPA Needed)

Plug your iPhone or iPad into your computer.

Most users recommend Sideloadly or AltStore for both Windows and macOS.