CheckMark was designed selfishly for personal use. There's nothing to install but it acts like an ap on your phone. It has a gold system, badges, awards and milestones to keep you engaged. You can color code, swipe left to delete, swipe right to send to the future and even share with a friend for support and validation. Advanced things like long term goals, regenerating tasks, the project library and the buddy system can all be grown into as you progress, so you won't feel overwhelmed.