watchOS 5.1 (16R5577c) for Apple Watch Series 4 (44mm, LTE) ✗ This OTA is not signed. OTA firmwares cannot be restored to. IPSW Downloads collects them for
potential future use. They might also be useful if you're doing research.
Release Date October 9, 2018 Upload Date October 5, 2018 Filename d626f9ee34a8837fb9ab93efe3e8f57f6a861ed2.zip Filesize 1.4 GiB Identifier Watch4,4
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