android-shuffle is another option. I've been using for quite some time and am very happy overall. It lacks a few of the features of Astrid, but it allows one to organize tasks by "context" (home, work, etc), and it will sync to a user's own server (running Tracks).
Posted May 5, 2011 8:33 UTC (Thu) by fb (subscriber, #53265)
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I also recommend Shuffle. Though it is only truly useful for people into gtd.
OI Shopping List is another choice: simple, open source and straightforward. I stopped using it because it lacks online sync. I could never get the point of Astrid 800 options.
Now I use a paid RTM account, as it has good sync and shared lists with an iPhone, allowing me and my wife to coordinate the groceries.