Just my suggestion. I don't use an actual Joomla Component to build my forms. I build all my forms using a program called Simfatic Forms (
www.Simfatic.com). Any form I want to be mobile compatible, I build it to the program's default width of 300px and it fits mobiles wonderfully. I do this form almost all of my clients. The forms look good on the PC and fit viewers screens when on phones.
You can see an example of this on my website. Simfatic is great for building forms that react to selects. If you go through my form like you were filling it out, you can see more fields come into play based on your selections.
www.JTLWebDesign.com 
