Wunderlist is a cloud-based to-do list management app.

TickTickis a cross-platform to-do list app & task manager helps you to get all things done and make life well organized.

Teamwork Projects is a project management app.

taskblitz is set of tools to collaboratively get your work done including project management, chat, time tracking and invoicing.

Todoist: To-Do list and Task Manager.

Any.do is a life management and productivity app.

ActiveInbox for Gmail is an email management software for Gmail.