I am sending gps coordinates from a windows mobile phone to a webserver using a basic program I wrote in C#. The problem is the data plan on the phone only allows 4 MB per month. I was planning on updating the location every 10 seconds.

Currently I am just creating a webrequest every 10 seconds to a php page on the server and the coordinates are passed over in the url, the php page saves them to the database.

This generates about 1K of data per request, at this rate I will hit my data limit in less than a day.

Is there a more efficient way to do this?