watchOS 5.3.1

watchOS

Version

5.3.1

Build ID

16U6600

File Size

160.31 MB

Release Date

2019-08-26T17:17:03Z

Update Type

Normal release

Delta update - requires 5.2.1 installed first.

Download OTA

Looking for beta firmware? View beta builds for Apple Watch Series 4 (40mm, LTE) →

About This Update

watchOS 5.3.1 (build 16U6600) is an official Apple over-the-air update for the Apple Watch Series 4 (40mm, LTE), released on 2019-08-26T17:17:03Z. The update package is 160.31 MB. This is a delta (partial) update that requires 5.2.1 to already be installed on the device - it cannot be applied from scratch. This update is no longer signed by Apple, meaning it can no longer be downloaded and applied on-device through Settings.

The OTA payload file is 9225d4ecea44aae5d800767a8182e1f96612a520.zip.

Direct URL

http://updates-http.cdn-apple.com/2019SummerFCS/patches/041-92185/E355C590-C501-11E9-8A11-875E50566A18/com_apple_MobileAsset_SoftwareUpdate/9225d4ecea44aae5d800767a8182e1f96612a520.zip