Things - Things is an easy to use task manager.
Trello - Infinitely flexible. Incredibly easy to use. Great mobile apps. It's free. Trello keeps track of everything, from the big picture to the minute details.
Everlist Task Manager - Groceries, trips, errands, and daily todos managed simply. get your tasks under lovely control.
Llama Life - Say goodbye to never-ending lists, and hello to daily bliss
Taskful - Deadlines, meet your match.
Flow - Stop managing projects from your inbox.