HTML5 Web Page to reverse geocode your location and display image from mysql database

General information for the website: Webpage which give location based information
Num. of web pages/modules: 1
Description of every page/module: The page should do the following:

1. Determine the current uk county you are in based on reverse geocode (from an iphone/android device)
2. Determine what month it is and time of day
3. Display an image stored in a mysql database based on the county which is returned in 1 above.
Description of requirements/features: This is the first part of a project for a web page which will determine your location and display images and text based on your location and date/time.

Further development is also required, based on the success of the above.
Extra notes: The end point for this webpage is a fly fishing web application which will tell you which flies are hatching on a river based on your location, month and time of day. The images and text will be stored in a mysql database. What I am looking for here is a framework which will retrieve and display information from to a web page based on the users location and time of day.