First, you're comparing two different domains. App developers (whether mobile, web, or some other environment) live at the top of the stack. As such, they must

First, you're comparing two different domains. App developers (whether mobile, web, or some other environment) live at the top of the stack. As such, they must wrangle many disparate frameworks and libraries to achieve their goals. Framework developers can focus on a narrower set of concerns--albeit sometimes quite deep. I would suggest that you stop comparing yourself to them and their achievements. Rather, use their example as a starting point in your pursuit of improvement. Many others offer good advice here, but one of the cornerstones is to look at what others are doing--often and deeply. Many have asked, "How do I become a great writer?" The answer invariably is, you must be a great reader. You need to read A LOT. The same goes for math. You must solve problems. That's the other half of the coin. You need to do. So pick a problem that hasn't been addressed. Maybe there's something you haven't found a library or framework for. Take the opportunity to build it, package it, and open source it. You'll see that the set of concerns is different from that of an app developer. Edit: typo