I think the point of Wunderlist was the online synching across devices and the list sharing. It was that there was some trust built up with the brand. I wouldn't just start using some random todo app and allow it to sync my todo lists without having some level of trust built up.
Something else that was critical is that I could use Cortana to add tasks to lists while driving or without typing on the keyboard.
I think when I want to go deeper in organizing tasks, todo apps are often bad for that simply because a document format tends to do better once you're in the thick. It's better if those things are stored, tracked and organized with the work itself most of the time and todo apps tend to be outside that context.
Something else that was critical is that I could use Cortana to add tasks to lists while driving or without typing on the keyboard.
I think when I want to go deeper in organizing tasks, todo apps are often bad for that simply because a document format tends to do better once you're in the thick. It's better if those things are stored, tracked and organized with the work itself most of the time and todo apps tend to be outside that context.