You can install IPA app packages to your iPhone, iPod or iPad from your computer. The same process is used to install an IPA package on your iOS device from either a Mac or PC. You can install an IPA package using iTunes for Mac or Windows while your device is connected to the computer with the USB cable. The IPA file must be accompanied by a provisioning file for your device, so you will actually have two files to install. The file extension for the provisioning file is “.mobileprovision.”
Transfer and save both the IPA file and the provisioning file to your computer’s hard drive. If you downloaded the IPA package in ZIP format, uncompress the ZIP archive to access the files.
Launch the iTunes application, then click the “Apps” tab in the left sidebar menu. If the left sidebar is not visible, click the “View” tab in the top navigation menu, then click “Show Sidebar.”
Drag and drop the IPA and provisioning file onto the “Apps” tab in the left sidebar menu.
Connect the iPhone to your computer with the USB data cable, then click the device name in the Devices section of the left sidebar menu.
Click the “Apps” tab in iTunes to view the Apps screen for the iPhone. The IPA file is listed on this screen.
Click “Sync” to install the IPA package on the iPhone.
IPA packages are often provided by developers for alpha and beta testing purposes and further development. Note that IPA files are not approved by Apple and can expose your devices to malware and harmful software. Only install IPA packages from developers and companies you trust.
Information provided in these steps applies to iPhones running iOS 7 and iTunes, version 11. Instructions may vary slightly or significantly for other versions of iTunes and iOS.