.ipa – iOS App Store Package
An .ipa file is an iPhone application archive file which stores an
iPhone app. It is usually encrypted with Apple’s FairPlay DRM
technology. Each .ipa file is compressed with a binary for the ARM
architecture and can only be installed on an iPhone, iPod Touch, or
iPad. Files with the .ipa extension can be uncompressed by changing
the extension to .zip and unzipping. .ipa files cannot be installed on
the iPhone Simulator because they do not contain a binary for the x86
architecture.
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