On checkm8-vulnerable devices (iPhone 4s through X), you can dual-boot iOS 6 or iOS 10 alongside your modern iOS. Once booted into the older OS, install the FIFA 14 IPA normally. This requires a jailbreak and technical skill.
While the hunt for the file continues in modding communities, it is difficult to run on modern iPhones. Because Apple stopped supporting 32-bit apps with iOS 11, the original FIFA 14 IPA usually requires an older device (like an iPhone 5s or iPad 4) or specific emulation software to actually play today. fifa 14 ipa file
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