First an offtopic “thank you”: I am new to your app and very happy it works almost everything. iPad broken and somehow my tasks have to be synchronized.
The bug: I’ve synchronized with iCloud and some tasks are viewed as duplicates. When I get rid of any one of those entries, also the duplicate disappears. Probably pressing synchronize button several times could be a clue to reproduct the issue?! If so I’say just prevent clicking while synchronizing and show a Status information. You probably could manage to program a detection for duplicated entries within tasks app so that will heal automatically since those seem to be linked by their external ID?!
And just a hint for advertisement - I’ve been searching for a clue if icloud tasks could be synchronized for about 15 minutes. You could more focus the ways the app can be used for in the description.