Any.do (6.7 MB), a very sweet To-do list app with alerts, speech recognition, cloud sync, backup and more. It's easy to use, press a task to change its priority, folder, alarm and note or share it; and long press an entry to move it around.
ColorNote Notepad Notes (535 KB), a handy note taking app in the form of text and checklist by color, with reminder, password, search and backup functions. You can easily schedule your notes and to-do lists in a calendar, pin a reminder on the status bar or stick a note on your homescreen via widgets.
Remember The Milk (3.4 MB) allows you to add and complete tasks on the go, organize tasks with priorities, due dates, time estimates, repeating, lists and tags, and sync with Remember The Milk online. Some features including unlimited sync and push notifications are only for Pro version.