I just went back to windows 8.1 (having been on Windows 10 for the last 3 months) and just realized how much I had missed it. For me, the usability of Windows 8.1 is far better than Windows 10 from a touch perspective. All the modem apps and the design style also seem to use touch much better than Windows 10. As an example, in the mail app, you simply click on one message to start selecting multiple messages on Windows 8.1. In Windows 10, you have to click a button at the top of the page to enable multiple mail selection. This behavior is found all through the OSes. Then metro ie is definitely much more touch friendly than spartan. I feel MS took steps back for touch to cater to desktop.
There are obviously features I prefer in Windows 10 but from a design language, Windows 8.1 is better in usability for touch computers I'd say.
Also, Windows 8.1 is very stable. If course with Windows 10 being beta, it's nowhere near as stable but I don't think I'm cut out for the beta life anymore (at least, for the next day or 2
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