Install AltStore on Your Computer
On your Mac/PC, install AltStore.
Once AltStore is installed, you will see a diamond shaped icon on the top right of your activity ray (bottom right for Windows).
Connect your phone to your computer with a cable. Click on the diamond shaped icon and install AltStore on your phone.
When you do so, you will be asked for your Apple account. This is to register AltStore as a developer app under your account. If you’re concerned about privacy, you can register an alternate Apple account with no credit cards attached.
After that it will install a plugin to your Mail App.
Open your Mail App > Preferences.
In the General tab, click Manage Plug-ins.
Install AltStore to your iPhone
With Apple Mail still running, click on the diamond icon and click install AltStore to your iPhone again. This time AltStore will be successfully installed and you can see it as a new app on your phone.
Before you can launch this app, you have to enable Trust.
Tap Settings > General > Profiles or Profiles & Device Management. You will see your Apple account as one of the developer apps. Tap on it and tap Trust [Your Apple ID].
Go back home and launch AltStore on the phone.
There are already a few apps on the AltStore you can install. Delta is the DS/GBA emulator.
When you install an app through AltStore, the app is installed directly on the Home screen instead of inside AltStore.
For PSP emulation, download PPSSPP for iOS on your iPhone.
Tap Download Latest IPA and download the file with the .ipa extension.
Go back to AltStore on your iPhone and tap My Apps. Tap the + icon the top left and select the IPA file you just downloaded.
PPSSPP will now be installed as a separate app.
Install PSP Games
To transfer PSP rom files from your computer to your iPhone, first connect your phone to your computer.
Open Finder and click on your iPhone on the left (under Locations). Click on the Files tab. Open another Finder window and navigate to the folder with your PSP rom. Drag and drop the rom file to the PPSPP app.
You may not see the changes on your Finder immediately but the file should already be on your phone. Launch PPSSPP on your iPhone and it should detect the file and your game is ready to be played.
If the file is zipped, you would need to tap on the zipped file and extract it with PPSPP.
If the game crashes…
If the game crashes on launch, tap Settings on the right side and tap Tools > Developer tools.
Tap CPU Core and select IR interpreter. Go back to the main menu and the game should launch without problems.
To save the game, click on the button on the top of the controls.
Click on a blank save state to save a new game. You can also load your saves or overwrite your old saves here.
Connect a Wireless Controller
PPSSPP supports wireless controllers without additional setup.
To pair a PS4 controller, on your iPhone go to Settings > Bluetooth. Then, hold the PS button and Share button on the controller until the back starts flashing. When your phone discovers your controller, tap on its name to pair.
Go back to PPSSPP and you can start playing with your controller right away. The on-screen controls will also fade out when you use the controller.
I hope you found this post helpful!