I feel I should learn one of the two main mobile languages. I own an Android phone, but I feel iOS is better to develop for (in terms of making something that could sell). However, there are external benefits to both that seem to favor Java; mainly, Java is used at larger enterprise places whereas Objective-C is only useful to make Mac Apps, and nothing really beyond that.
I can't decide, because they both seem useful. I have no other inclinations (I wish to continue development as a ruby dev, so this isn't terribly influenced by future career choices).
What are your thoughts?