I agree totally with you. Enterprise is really where the big stuff happens, which is why I have jumped into a new job that's going to push my Java skills through the roof. Although I do sometimes feel that Java is the current world's equivalent to the 90's Cobol.
Great marketing got these companies to buy into it and now they are bound to it even though there are newer, more efficient methods to achieve the same goals.
You should also consider writing apps for smartphones and tablets.
Currently about 16.7 % of cell phone users own smartphones.
http://mobithinking.mobi/mobile-marketing-tools/latest-mobile-stats/a#smartphonepenetration
It might be tempting to interpret that stat negatively by saying its a small market why bother, but actually that indicates room for growth.
Even in the US, less than 50% of mobile phones are smartphones.
The next step up from smartphones is a tablet. There is some market research that shows that its a natural progression for consumers to migrate to a smartphone, then to a tablet, although obviously not implying that everyone with a dumb phone will get a tablet
The biggest market is currently iOS for the iPhone and iPad, which requires Objective C skills. It's an easy language to learn, as its a subset of C. A lot of the difficult bits about C are hidden, such as memory management.
I say easy to learn, only if you already do development. And web design is not development

If you are getting paid to write code on a daily basis, then you can, with EFFORT pick up java, objective C etc.
Android is getting more popular. It's basically java.
Java and IOS are not that different although you can't share code.
http://m.infoworld.com/d/developer-world/developers-eye-view-smartphone-platforms-565
And let's not forget about HTML 5, although, even in the US, a lot of people feel that the risk of latency and dropping connections is still too high for many mobile applications that require regular networks just to refresh a screen.