Mobile app development For Firefox Mobile?

[Reptar38]

Hi, I just wanted to know that if I wanted to get an addon made for firefox mobile, what type of developer would I need to hire? What I mean by that is what language is firefox addons written in?

Anyways, I was speaking to some local Dev's at unitxy that gave me a quote but I would also like to hear from anyone else that has had an app developed as this is my first time. Has anyone used them before? Or Do you have other companies that you've used which I can get a quote from?

Any help would be appreciated!

Thanks & Regards,
-Jake