EssentialPIM - EssentialPIM is a free Personal Information Manager that keeps up with the times and lets you manage appointments, tasks, notes, contacts, password entries and email messages across multiple devices and cloud applications.
YourHour - YourHour is an app by Mindefy labs through which you can easily overcome with your phone addiction by monitoring your phone usage.
Todo.txt - Track your tasks and projects in a plain text file, todo.txt. A todo.
21 Days - 21 Days app enables the user to track their habits to take challenges to adopt good habits.
Task Coach - Task Coach is a simple open source todo manager to keep track of personal tasks and todo lists.
iBetter - iBetter app comes up with features to help you in fighting bad habits and developing new habits through your smartphones.