A modern programming language that makes developers happier.

kotlinlang

I wrote about some hidden gems/things I don't think get explained to new Kotlin devs often enough. <https://tech.okcupid.com/hidden-gems-in-kotlin-stdlib/>

I thought actually something "more" hidden

Yeah, they're not the biggest secrets, but for beginners I think these are a lot of things that don't get explained often.

I presented this at a meetup Tuesday and most people said there was at least one thing in here they didn't know about.

About `supportsLollipop { ... }`
In my opinion, you should definitely add that to your project is that's useful for you. The arguments against adding them to a general purpose library apply only there. You don't care about not breaking backwards compatibility in your own project where you can refactor as you wish. I would just put more context. Like if your app use Bluetooth, you probably want to have 
`supportsBluettothLE { ... }` instead of mentioning lollipop