All of these look important to me, but I've been particularly frustrated recently by the smartwatch issue. I've been a Fitbit user for several years and briefly tried an Apple Watch before returning it and resume Fitbit use— I had a few issues with the Apple Watch, most notably around battery life. But that brief experience showed me really starkly how much Apple is able to lock out third parties from doing things that their own stuff can do trivially by hooking right into private operating system APIs:

- Apple Watch can directly use your credit cards without needing to separately add them to Fitbit/Google Pay.

- Apple Watch can "find my" your phone, whereas Fitbit's version of this is limited to just making it beep, and even that only works if the phone is running the Fitbit app in the background (which it often isn't).

- Apple Watch can stream data to the phone all the time, whereas Fitbit relies on the app being opened, meaning your morning sleep data isn't available immediately since opening the app (to look at it) just enables it to begin transferring.

- Apple Watch can unlock itself when your phone unlocks.

- Apple Watch gets much richer notification integration.

And yeah, you can argue that all of this is optional "extra" stuff that is just Apple's prerogative to take advantage of as the platform holder, and maybe that's so to some degree... but these little things do add up. Particularly when Apple doesn't even have a device that competes with Fitbit, it feels unfair that they shouldn't be made to open up all the APIs necessary for this kind of interoperability.