It would be interesting to have a simple task and personal task management application  (Like Wunderlist), which can be installed as a separately app on the mobile.

It would also be great if the app have integration with the mail and calendar.

I know there are Projects, but in this case it is something simpler for people who only need to add tasks and subtasks with reminders and due dates.

Would be a great alternative to Microsoft To-Do, Google Task, Todoist, Tick Tick and many others...

Thank you :)