I was a huge Windows Phone advocate around this time, and indeed in many markets _outside_ the US it had periods of being the #2 behind Android. To my vague rec

I was a huge Windows Phone advocate around this time, and indeed in many markets _outside_ the US it had periods of being the #2 behind Android. To my vague recollection maybe India, Mexico, and parts of Europe (where it was sometimes #2, and when not at least had a much stronger showing than in the US). There was solid user research at the time indicating that it was both more popular with and had a lower learning curve for first-time smartphone buyers compared to iOS/Android at the time--but there were fewer and fewer of such first-timers by then. IMO it's a great example of a better platform (in terms of UX and polish) losing to competitors/incumbents on things other than...for lack of a better word..."worthiness". As @chiph said, being the third to launch is just a death knell for platforms. The network effects trending towards a duopoly are just so strong. I worked for an agency where clients did initially give us budget to build WP apps (and we had a ton of fun!), but if you make an 80/20 decision enough times, you end up supporting only the top 2.