Modern app development uses 64-bit architecture. iOS 7.1.2 relies entirely on older 32-bit architecture. When you open the modern App Store on an iPhone 4, you will find that 99% of apps refuse to download, stating they are "incompatible with this iPhone."
: A modern tool that often maintains support for older devices to "inject" IPAs. Legacy iFunBox or 3uTools ipa files for ios 7.1.2
For advanced users, command-line tools offer a more direct method of downloading specific versions of IPA files directly from Apple’s servers. One of the most prominent tools in this space is , a cross-platform utility available on Windows, Linux, and macOS. IPATool uses a valid Apple ID to authenticate with the App Store’s backend, allowing users to search for apps, purchase them (even if they are free), and download a specific version by its external version ID. Modern app development uses 64-bit architecture