I have tasks, two calendars, contacts, and email synced between MacBook Air and N9. I use Google for contacts and two calendars, but it is famously hard to get Google tasks synced, so I don't use it for tasks. Instead I use a plugin for the Mac to sync my tasks (in iCal) to Todoodle and Nuevasync syncs my tasks from Todoodle to the N9. Meanwhile Nuevasync also syncs the Contacts from Google and one of the Calendars from Google - it has to sync the same calendar that has the tasks in my Macbook, otherwise I won't get the tasks from Todoodle. The other calendar is on a different Google account, and I use CalDav in the N9 to sync that. That way the two calendars are preserved as two separate calendars in the N9 (hooray! never could do that with the N900). However I do NOT use Nuevasync for email sync, even though it would be nice to have push email. The email account has a lot of folders in it and, like with the N900, it is not possible to only sync a subset of folders with Exchange in the N9. Trying to do so resulted in a 14 hour sync and it still hadn't finished, and lots of messed up stuff (the Exchange client is still quite buggy). So I just sync the email using the native N9 email client, so there's no push email, unfortunately. Nuevasync does have a solution to prevent any folders under a certain specially-named folder getting synced as a workaround, and implementing that -- if you have a lot of folders -- you could also get push email, too.