The WordPress app for Android just got an update with a pretty nice and new editor. Now it doesn't only support plain text or HTML editing. It got enhanced to support all the text formatting, quoting, listing etc. too.
The update is still marked as RC (release candidate), that's why you need to be part of the beta community or download the APK elsewhere.
You can ask to join the beta community on Google+Â here.
And here's a screenshot of how the new editor looks like: