Hi, my name is Martijn, CEO at MAPPZ Development.
I started development back in 2011. I began with porting the APK Multi Tool (link) (for Windows) to Linux, with some help of my dad. At the end, the project failed because I didn't have any backup (that never happened again).
I gained more experience with my own project developed in Python: StudioAndroid. It's a tool for every Android tweaker, modder, developer and themer and could have been be used for simply everything. Because I started Android development, Studio Android is now kind of a side project.
I started Android development (which is done in Java) in December 2012, and look what we've got already. MAPPZ QuickSettings and MAPPZ QuickWidget (coming soon) are my proudest projects. Go and have a look at them at App Development!
Summarized: We have lots of experience with development in Bash, Python and Java.