Now you have to Open iOS settings and go to the General section.

You need to jot down or remember the name of the developer from the error message box.

Step by step guide to fix Untrusted Developer Error

Note: you may see the Untrusted Developer Error while visiting Appvalleyapp because it is an unofficial app. Wait until the GBA4iOS’s installation gets completed.First of all, Navigate to /gba4ios/ from your device.However, GBA4iOS helps your device to emulate console games without Jailbreak. Most of the GBA emulators require you to jailbreak your device. How to install the GBA4iOS emulator on iOS without Jailbreak The best part which I forgot to mention is that it does not require your device to be jailbroken.

The updated version is packed with a lot of marvelous features such as options to display the game in landscape or portrait layouts, save states, skip frames, and fast forward for quicker gameplay. However, the developer of this console made it open-source which encourages the freelance dev to keep it alive. The development of the GBA engine ended a long time ago. The GBA emulator provides a very powerful game engine which has many highly-requested features such as AirPlay, Dropbox sync, Cheats, iPad optimization and lots more. Mario series, and Pokémon are the most popular console games which you can now run on your iPhone device.

GBA4iOS is a portable game boy advance console, created by iOS developer Riley Testut, for playing GBA or GBC (Game boy color) games right on your iPhone device.

The best gameboy emulator for windows