I have been using ToDoist for over a year. I am only using the free version even though I know I would benefit from the features you pay for. The biggest reason I began using it was the mobile app. Being able to look at my daily tasks on the phone and take care of them while out of the office or away from home was a big benefit.
While all of the ToDo List websites had mobile apps, this one was simple. I didn’t want to get to complicated. Here is the task and check it to complete it. Combine that with IFTTT which will create ToDoist tasks given certain triggers and you have an unlimited amount of work to accomplish. That’s what we all want right? More work! 🙂