Most of those are not truly Free, or at least not much freer than Android.

- Maemo: open middleware, closed many applications and some drivers

- OpenMoko: closed drivers

- Symbian: was it ever libre?

- Meego: same as Maemo

- Mer: this is actually open AFAIK, but no native devices I know of

- Jolla: Android kernel (closed drivers), closed applications

- Tizen: ?

- Ubuntu Touch: Android kernel

- Firefox OS: Android kernel

- Web OS: ?

Only a couple of the above really matter in this light.