, version 1.2.1 is one of the earliest standalone YouTube apps for iOS. Historical Context
Use a modern PC to download YouTube videos as .mp4 files, then sync them to your old iPhone via iTunes (or a third-party tool like 3uTools). This bypasses the app entirely. Youtube 1.2.1 Ipa Download
Because this app is no longer available on the official App Store, users must utilize an file and side-loading tools. , version 1