Meego was Nokia's suicide note
Maemo might have been a contender. We'll never know. It was the hottest thing one year (2010, I think) at FOSDEM, only to be made abandonware a couple of months later as Nokia drifted to Meego.
From that FOSDEM, Maemo had a real developer community, and it looked like a possible challenger to the then-dominant Iphone. As soon as we were abandoned, Nokia lost itself that community and ceded whatever chance it might have had to Android.