I was in the middle of coding some application for android and I needed a File/Folder browsing dialog. But I also needed access to /data and other sensitive folders. So I started searching internet, but I didn't find anything useful. Anyway, I decided to write my own. For initial code, I used sample project from here
I started expanding it, made some changes to it, added images for files and folders, added root access features, added known filetype icons, etc.