If I purchase the pro version, will I be able to sync my tasks between multiple computers? For example, if I changed the due date, category, and repetition of a task on one machine, will it sync to all machines running the pro version? Maybe this is possible if the location of the local folders is stored on Dropbox?
If you use a cloud account like Google which has Gmail, Calender / Tasks etc then everything syncs on all devices the same everywhere. Even the free EMClient will do that. The Pro EMClient just mainly lets you have more than 2 accounts.