If you are a tinkerer with a jailbroken iPhone 4s, do it for the nostalgia. Open the app, scroll through a 2016-style News Feed (no Reels), and smile. However, if you need reliable, daily communication, sell the iPhone 4s to a collector and buy a cheap iPhone SE (1st gen) on iOS 14.
If you found an IPA online, you can sideload it using Sideloadly (works on modern Windows/Mac) with a free Apple ID. However, iOS 7.1.2 does not support the modern AppSync or developer disk images easily — you may need a jailbreak. Facebook Ipa Ios 7.1 2 Download
Given how unstable the 2016 Facebook IPA is today, I strongly suggest using on iOS 7.1.2. If you are a tinkerer with a jailbroken
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