Platform: iOS, Android
Developer: Fog Creek Software
Trello is an online organisational system that differentiates itself from other to-do lists by acting as close to virtual Post-It Notes as we've ever seen. You create boards, and then add lists to them. These could be 'To-Do', 'Working On', 'Completed' or whatever. Cards are individual tasks, and you simply drag and drop them around the board. It's a brilliant system that offers superb visualisation of your tasks, and the free version works beautifully. Trust us, you need this.