> The other thing that killed them, as many have noted, was the lack of apps. ... What app developer wants to spend a lot of time and resources developing a 3rd version of their app for a new platform that no one is using yet?
Sure, there was a lack of apps; but it wasn't all because it was too late; Windows phone 7 wasn't _that_ late to the game, and there's value being the only app for X on a platform, even if it's the smallest platform. The problem was your windows 7 app didn't work right on 8, and you probably should rewrite it again for 8.1, and you definitely need to rewrite it for 'Universal' Windows Platform for 10, except that's a waste of time since 10 never got anywhere close to the number of users as 8.
If Microsoft hadn't effectively killed Windows Mobile 10 by merging the desktop and mobile teams during development, and ended up with a solid Windows Mobile 10 release at launch, they would have been able to continue as a third platform. Supporting WP 8 devices upgrading to 10 and continuing to release lower end devices on 10 would have helped get existing developers to update their apps for 10. Having a decent browser would have helped, but Microsoft was playing the 'pretend to be iOS' game too hard, and blocked browsers from the store until it was too late; Firefox wanted to release for WP, but Microsoft said no, and IE/Edge are IE/Edge.
Given all of the things Google is doing to try to rein in apps, like Doze and this storage api revocation; it would be nice to have an option that isn't iOS.
WP 8 may have been ugly, but it was functional, and had a dark mode _everywhere_. The better tiles were really useful for getting the right amount of information, and because they were a critical part of the UI design, most apps supported them, unlike launcher widgets which are pretty hit or miss. Number badges require you to go in and reset the count to zero or they don't provide a useful signal; seeing the last message lets you delay it to later.