Originally Posted by
Mike Gibson Using a "completely different kernel" doesn't mean anything in terms of backwards compatibility with hardware (e.g. you can run Win95, WinNT, and Linux on the same computer with no problem). Either the WP7 hardware was lacking a specific feature MSFT wanted to use in WP8 ... or the WP7 hardware was simply too low spec'd to give acceptable performance in WP8.
Just because you can, doesn't mean it's easy. Especially when you are talking smartphones with low specs, carrier dependencies, and other variables the leave room for many errors.
Microsoft took the safer route of starting fresh. It burned a few people, but wp7 market share was pretty insignificant. I was a WP7 user from day one, and wasn't **** hurt at all by upgrade issue.
WP8 -> W10 is a different story. MS can't break that.