Apps are always nice, but lots of mobile websites, including the kbin one, are entirely functional as an app. In your browser you can just make a shortcut to them, and they'll appear on your home screen and act as an app.

In technical terms these are Progressive Web Apps, but it means you don't need to wait for someone to write an app (or kbin to have a good API for doing so) to use it like an app on your phone.

In Firefox it looks like this. Open the website, in the menu hit Install, drag the icon to your desktop. When you click on it it'll open the site like it's a standalone app.

Chrome is exactly the same, but the menu button is "Install App" instead.