watchOS 5.1.3 (16S535) 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 January 22, 2019 Upload Date January 11, 2019 Filename 8b7ee66d1c13602a555dace37f8137999fd08aa5.zip Filesize 1.4 GiB Identifier Watch4,4
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