The era of easily installing an is ending. Within 2-3 years, it will likely be impossible without a jailbreak (and jailbreaks are nearly dead for modern iPhones).
And they will detect it. Facebook’s servers see your client version. If you connect with v100 when v400 is current, they will display a banner: "Update Messenger to continue." Eventually, after a week or a month, the old version will stop connecting entirely. This is a . Part 9: The Future of Old IPAs As of 2025, Apple has aggressively moved to kill sideloading in the EU (under the DMA, they allow alternative marketplaces , not arbitrary IPAs). In the US and globally, iOS 18 made app signing even stricter. Messenger Ipa Old Version
However, for the nostalgic power user with a jailbroken iPhone 6 on iOS 12, running Messenger v120 feels like a time machine—no ads, no stories, just pure, fast texting. The era of easily installing an is ending