It's weird that lots of people keeps hyping Java for mobile phones but AFAIK there are no killer apps on Java on mobile phones! Why? Two big reasons: 1. for whatever reason except for Microsoft, there doesn't seem to be any real developer community 2. Java (I know it's not Java but the implementation of the Java APIs but Java without complete implementation of the relevant APIs is useless) can't do anything but the lowest common denominator e.g. not being able to take pictures at full megapixel resolutions is a show stopper for many photo related apps methinks.
Here's my proposal, forget the smartphone and deploy something that can be used with simple Java phones. Indeed, I've seen some cool stuff there, too, but nothing out in the wild, yet.