I have to agree with Ged Maheux on the incessant Activity app on iPhone and Watch.
The longer my streak continues, the more pressure there is not to break it. It can be so stressful in fact, some people have come up with clever hacks to work around breaking streaks. Contrary to what the folks on Apple’s Activity team may tell you, this isn’t actually healthy. It’s important to give your body (and mind) a break to recover and rebuild every now and then. Which is why iOS desperately needs to build in the concept of rest days into its Activity app.
A rest day. Great.