Together with a redesigned Gmail, Google also announced a new standalone app for Google Tasks, a web service that was formerly only available through Gmail and Google Calendar. The app is available on both Android and iOS platform.
Google Tasks is a task management service, where it users can create tasks as reminders. Subtasks can also be added to existing tasks with additional detail. The app is still available through Gmail and Calender, which means you can still add tasks through the pair. The app will remind you when a task is due for today.