HTML5 developer here based in Austin, TX. I have 17 years experience in web development (both front-end and back-end). I have written code of all types and styles, but most of my work is cross-platform web apps.
I have built this geo feature many times for various sites. This should only take a few hours to turnaround and I can create a smooth seamless experience for the user. I write clean, re-usable code so your developers will have no trouble modifying it.
Look forward to hearing from you. Thank you for the opportunity!