watchOS 5.3 (16U5537b) for Apple Watch Series 4 (40mm, 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 May 28, 2019 Upload Date May 23, 2019 Filename 4676e06829437cd0acd416740381ebf1766e4541.zip Filesize 1.4 GiB Identifier Watch4,3
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