Nemo's the place to look for middleware-type things like this. Buteo is where most synchronisation-pieces live. Keep an eye on e.g. https://github.com/nemomobile/buteo-sync-plugin-caldav. *edit* yes, it's empty at the moment, but work has started - it just hasn't been reviewed and had the integration process started, so I'm told.
Dear Enemy: may the Lord hate you and all your kind, may you be turned orange in hue, and may your head fall off at an awkward moment.
How to tell Heretics from Catholics?Papal legate Arnaud Amalric answers :Caedite eos. Novit enim Dominus qui sunt eius.(Kill them all, the Lord will recognise His own.)
“Get thee to Hell, where Asmodeus himself may suckle upon your diseased teat!” Barnabas Collins