[tomsem]

The BT keyboard I'm currently using using (3-4 year old Logitech) will pair with 3 devices (any OS), selected via assigned keys. It's a little heavy but no doubt there are lighter ones with the same functionality (this one has a couple of AA batteries in it, which I've only had to replace once). I also have a much lighter Anker with rechargeable battery, and that goes for probably a year between charges, but pairs with only one device. I think it also goes to sleep sooner and so you have to get used to waking it up before typing.

I'm planning to get an iPad Pro, but don't see myself getting Apple's SmartConnector keyboard and throwing away the flexibility. There's talk of more 3rd party vendors using it (I think only Logitech does now) but its not clear to me there is demand. It's not really very onerous to charge a keyboard every year, and I don't find latency much of a problem.

I wish more app developers would think to include keyboard use cases (hotkeys etc). Specifically reading apps should at least respond to arrows to turn pages, Enter or space bar to scroll, ,command+F to initiate search etc. Apple's apps do well with this for the most part.