I am a frontend focused full-stack engineer with 7 years of relevant experience in the frontend engineering space and a total of 12 years of experience. I am not able to decide where should I invest my time when working on side projects. Should I start picking up mobile(Android/iOS) or continue to sharpen my skills in the frontend development space? To put it another way, should I invest my time in going depth in my current domain or should I invest time learning mobile UI development as that has gained more traction and is viewed as more valuable skill?
I think I am unable to decide whether to go about developing my skills in breadth or depth.