It was always the best native experience on Apple platforms - they won an Apple design award, but they were always slow to update (Another reason I attempted to look elsewhere). Personally, it was also the most “natural” todo app I have used. It fits my mental model extremely well with a light but not onerous GTD model. 

Last month they released version 3… and it’s absolutely amazing. The amount of care that went into every UI element, action and animation is simply incredible. 

I admittedly hesitated to buy it for a few days as it is one of the most expensive suite of apps to buy, but I finally obught the iPhone app today and was blown away. 

This is the app that allows me to stay organized - so if you are in the Mac/IPhone ecosystem, I can’t recommend it enough. But even if you don’t want to buy it, I think it is worth watching videos one the UI or at least buying the iPhone version to play with it and study the UI. 

One last thing, it is on sale right now. So if you are tempted you may want to grab it soon.