I have switched from Wunderlist to Trello, Trello is much more better, but with a big lack: no offline MacOs App (as Wunderlist had).
All the Trello Apps in the MAc App Store don't sync cards that have been added while computer has been online. This is a big problem, you even don't know that the card will disappear next time you relaunch the app. This is definitely against the spirit of GTD: you need a relayable inbox .
It could even be OK if you cannot edit/move cards.
Just a offline working inbox...
On the other hand, Wunderlist manages very well offline modus, never lost any list item. So this should net be to complicated...
Thx