Remember The Milk - Remember The Milk is a task and time management application for mobile devices.
Day by Day Organizer - Time management app that combines Google Calendar and Google Tasks and enhances their features.
Top Task List - Top Task List is simple, elegant and responsive task organizer.
Calendar Lock PEA - Calendar Lock PEA is an encrypted desktop calendar with a day, week and month view. The shown calendars are never stored unencrypted on your disk, but exist only in the RAM. Platform-independent, Open Source, no installation or registration required.
TimePanic - TimePanic is an award-winning application for tracking time spent at the computer.
Business Calendar - Powerful and easy to use calendar app for Android including weather, widgets and tasks.