Qibla Finder APP
If you are not willing to fix your location for some reason, you can also select where you are from the database that resides in the application. All the towns that has population more than 15 thousands as of 2012 are listed in the included database.
In order to conserve battery and speed up finding direction, you can select your location from database. If you are not very close to Qabe, e.g. you are not in the city of Mecca, frankly, your error will be negligible.
If you use one of the location fixing methods, after a fixation on your location occurs, application will try to calculate nearest five town centers to the fixed location. So that you should check and see if application reads your location right.
Magnetic declination is a function of time and space. It changes by traveling on Earth or by time. A prediction is done by National Oceanic and Atmospheric Administration of USA. Their coefficients and formulation is included in the application. These predictions will expire on 2020. So when we get close to 2020, you will need to update the application.