I have a Lenovo s2110 Tablet and a Razr Maxx. Both have aCalandar+ installed on them but the Tablet will not sync. When I had the free version of aCalendar installed both devices synced fine. I am using my gmail email acct to sync. I installed a different calandar app thinking maybe it was the app but the same issue happened with the new calendar app. So something is wrong somewhere on the Tablet. I did go into Settings > Accounts & Sync and the email address is set up properly and syn is ON. Any ideas of what to do??