I just got my Jolla phone a few days ago, and now I'm investigating
porting SyncEvolution to it.
Since Sailfish is based on Mer (the fork of Nokia's MeeGo), the base
platform seems very similar to Harmattan. From what I can tell,
QtContacts and KCalExtended is still used on Sailfish, so the existing
SyncEvolution backends can probably be used.
The SSO implementation on Sailfish, though, is also based on Nokia's SSO
implementation. From what I can tell, this implementation is from
Ubuntu. It seems to me that Sailfish is using the SSO implementation
from Ubuntu Online Accounts.
Then, what's the plan for supporting UOA in SyncEvolution?
If I have to, I could try to change the gSSO implementation so that it
can deal with the Ubuntu implementation, but I don't run Ubuntu myself,
so I'd only actually test it on Sailfish...