OmniFocus alternative for Android?

I used to be an all-around Apple product user, and OmniFocus is one of those apps that I can barely live without. However, I'll be using an Android phone for the next year or so and OmniFocus have not (yet?) released an Android version of their app. Is there anything for Android that comes close to OmniFocus for a GTD-based todo app? Paid apps are perfectly fine, after all I was willing to pay $140 to have OmniFocus on all three platforms it supports. Ideally it would have an app for both Android and iPad (an OSX app isn't that important but would be kind of nice) and cloud syncing.

I've tried setting up a custom system using Evernote/Simplenote but I'm not happy with that solution.