Just in case you weren't aware of Appigo's Todo, a simple task management tool for the iPhone, we wanted to make you aware of it. We're currently in the process of adding many more GTD-like features, but so far, we've been getting some great reviews on the App Store.
Rather than blasting users with every possible option available in normal task management software, we're taking a phased approach to make sure that the user interface remains simple and pleasant to use.
One of the key advantages of Appigo's Todo is that it can synchronize directly with Toodledo.com and Remember The Milk.
You can watch a full overview video of how it works here: http://www.appigo.com/todo/