Before I go too deep down this rat/rabbit hole, I should state that Libraries are what has allowed programming to develop from where only the best of the best can produce software to a place where a plumber like me can still produce some pretty amazing stuff.
KendoUI is one the most popular mobile frameworks around, and for good reason. Until a few months ago it had a commercial only license which limited its attractiveness to non-enterprise developers, but its new Apache license makes it very attractive especially if you are looking for a framework that heavily leverages jQuery.
When mentoring a new programmer I almost always try to force them to learn two things, Regular Expressions and VIM. Although both are relics of a bi-gone era (I still think it is hilarious VIM popularity currently is, I expect EMACS t o swing back into vogue any day now). I still use each one every day, and save myself hundreds of hours a year simply because I can do things very quickly that take someone unfamiliar with those tools much longer. I am pretty good at VIM, and pretty good a regular expressions (though definitely not a master in either), however I feel that people who develop in VIM or Sublime or any IDE or Editor that doesn't have constant static analysis is making life harder for themselves and overly relying on tests to do their typo checking for them. Use an Editor for editing text and an IDE for programming.
When I first started programming, I tried to write the most compact, cleverest blocks of code which I would dutifully comment to explain what they where doing. These comments where odes to my brilliance and what a clever way I had solved this problem rather ...
Bootstrap is another monster in the mobile world now, especially with Bootstrap 3.0 and its emphasis on responsive and mobile first design. And it can't be argued that it is popular, a lot of the sites you see created in the past few years are written with the aid of Bootstrap (or perhaps Zurb's Foundation)). It provides a great way to get a website up and going, and looking good with as ...