Yeah, I just did some testing on an Android device as well and had the same result. I like Slate's API and data model more than Draft's, so I'd almost certainly switch if this were fixed.
I'd guess that there are definitely some x-browser issues with Android right now because I haven't tested there at all. So far I've been working on the core pieces of the library, and making sure desktop works. A few folks have contributed iOS fixes for things like autocorrect. I'd love for any contributions that make things work better on Android! (Or other platforms.)
Thanks!