Hello Dear, I've read your project description and I can design and build an mobile app service for your project as per your requirements with complete mobile responsive design. What is the nature of your mobile app? Let's have a quick discussion about the project.
We have extensive experience in designing and developing Portals, Web and Mobile application, E-commerce in all major platforms, etc.
I am sharing our portfolio with you have a look,
https://www.freelancer.com/u/junkyfunky
Thanks,
Faizan