In my experience, technical questions aren't usually language-specific per se. Instead, they focus on algorithms & data structures. Are you getting a degree in Computer Science? If so, you should be pretty well-prepared for technical interview questions already.

AI and Machine Learning are very interesting fields, but you need a deeper understanding of CS than you do for mobile/web development. Just out of curiosity, are you familiar with what a state-space search is, and the difference between breadth-first and depth-first?

edit: FYI, I'm also C.S. major graduating this semester. I consider my interests to lie in AI and ML as well. I've not had any trouble with technical interview questions.