Yeah it auto connects if BT is on the iPad, and I switch ON the keyboard from cold, but if it's already on I have to do it manually.
Can't be bothered constantly switching the Apple keyboard on and off. I know it's a nothing task, but I'd be switching it on and off about 20 times a day the way I use my iPad. It'll be sat on my desk one minute, then I grab it whenever I go do boring stuff in the house while listening to podcasts.
My BT earphones connect in the same manner.
The only device I've had that autoconnects regardless of all of the above is the Apple Watch.
Not heard of that MS keyboard, looks interesting. I see that it sleeps/turns off when you fold it, that means it'd likely reconnect automatically when switching on, or switching devices. Hmm. Need to investigate if the media short cut keys work seamlessly with iOS, that's a key function I'm interested in, don't actually do that much typing on my iPad, but like the option.
Edit: Bought that keyboard, ha! A few YouTube vids show it should work in the manner I want, got it from Amazon anyway so can easily return if me no likey. It's a better option than either Apple (wired or wireless) for the purpose I've got in mind tbh, thanks for the info!
Edit 2: Received said keyboard, works exactly in the manner I wanted. Simply flipping it shut disconnects, opening it up reconnects automatically. Brilliant. Will take a little getting used to that gap in the middle, but I'm sure it'll be great for email and media control, largely what I'll be using it for.