There is a real successor to the N900 called Neo900:
Still in development but some really cool stuff like isolation of the modem.
Re:Plasma Mobile
by walterbell on Sunday July 26, 2015 @12:40AM
(#9950166)
Did you consider Jolla/Sailfish?
The experience, speaking as an n9 user who eventually moved to Android, was much more pleasant on the n9. The only problem was limited app selection.