This chapter covers two of the facilities in Windows Phone 7 that provide information about the outside world. With the user’s permission, the location service lets your application obtain the phone’s location on the earth in the traditional geographic coordinates of longitude and latitude, whereas the accelerometer tells your program which way is down.
The accelerometer and location service are related in that neither of them will work very well in outer space.
Although the accelerometer and the location service are ostensibly rather easy, this chapter also explores issues involved with working with secondary threads of execution, handling asynchronous operations, and accessing web services.
Windows Phones ...