watchOS 5.1 (16R5577c) for Apple Watch Series 4 (40mm) ✗ 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 98f28bcf15c7b0d98d1a156b203c075ea0f85c9e.zip Filesize 1.3 GiB Identifier Watch4,1
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