I should have mentioned or asked you this earlier, have you checked to see if your device is compila

I should have mentioned or asked you this earlier, have you checked to see if your device is compilable with FF Mobile & supported?

See:

Will Firefox work on my mobile device?

Had an issue such as this today where everything met min specs except it was Targa 2 platform whith 4.1.1 jellybean OS. Honestly mobile seems to be rather buggy and picky lately, seen lot more problems both personally and come through here.