First pick a platform, are you more interested in native mobile or something web based. I primarily work with PHP but I've also tried Ruby and Python. Either on

First pick a platform, are you more interested in native mobile or something web based. I primarily work with PHP but I've also tried Ruby and Python. Either one could be my next. Truth be told, just make sure you keep asking "why" and understand the basics. After that, switching to a different language will be pretty easy and you'll mostly have to worry about learning the popular frameworks and libraries.