I use it for heartrate monitoring. It’s disappeared from my watch with the latest update and no longer appears on the list on the Watch app on my phone. IOS 15.6.1.

Apple Watch App Gone

Run.10K.Every.Day (Stuart Middlecoate) June 2, 2023, 9:10am 7

I’m not an apple man but i know the latest version needs iOS 13 as minimum. Is it the case your phone that’s linked to your watch is older?

Have lost the companion app from Apple watch

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