What are the challenges involved in creating an app like InstaMapper for android

http://www.instamapper.com/android

I am planning to dive into android dev and i have a pretty good java and web-dev background. i was planning to develop an InstaMapper type of application and i need to know the challenges in so basically the things involved in gps tracking an开发者_JAVA百科d displaying the information on web page..

In simple words,

1. You need a web service.
2. You need an android app.

Your app will collect the (Latitude,Longitude) pair from your GPS receiver and sends it to your web app.

Your web app will get this values and store them in a database.

To display the path from (Lat,Long) pair, you need to implement Google Maps API inside your web pages. (Google Maps API: http://code.google.com/apis/maps/)