If GPS is one of the key requirements, it may be a good idea to consider the following aspects before choosing a phone.
GPS v/s A-GPS
Standard GPS requires a line of sight connection with at least three GPS satellites to find the exact location. Moreover, the satellite feed should be available for 30 seconds to a couple of minutes before the GPS can provide exact coordinates. This can lead to significant problems if the user is surrounded with tall buildings, trees or is indoors. Also, a GPS has to perform complex mathematical calculations using triangulation techniques to determine the position-based on the satellite signals. Therefore, the start-up time for any GPS-based application can be frustrating. This problem can be solved by using an advanced technology called A-GPS or Assisted GPS. In the case of AGPS, the GPS unit contacts an intermediary called assistance server, which helps determine the location of the device much faster. The assistance server can use the cell-phone tower information to start the computation process and also performs complex mathematical computations on a much faster processor. This provides following benefits:
- Device location is determined much faster
- Location can be acquired even when there is no continuous satellite signal available
- Device has to perform less computation leading to less battery consumption
However, A-GPS requires an active data connection and if one is not on an unlimited data plan, its usage can lead to increased phone bills.
Since GPS-enabled phones will be invariably used for navigation assistance, it’s important that the screen size is reasonably large to enable easy viewing of maps and driving directions. Higher screen resolution can add to enhanced experience. Hence, compare the display resolution before finalizing your phone. Another good feature to look for should be ambient light adjustment. Many cell phone displays can increase or decrease display brightness depending on ambient lighting conditions. This is very useful when one is walking in bright sunny outdoors.
If the objective is to make your phone double up as vehicle navigation system, it will be a good idea to buy a phone, which comes with accessories to mount it on a flat surface. This can be very handy if you use it in your car. One should avoid flip-phones because they are not very useful when it comes to using them as navigation systems.
Needless to say, GPS antennas and overlaid applications can be a big drain on battery. It will be good to have your phone with enough battery when you need to make that late evening emergency call. Phones with external charging accessories can be a better deal.
Many GPS applications will require on-device storage of static or cache data. The bigger the storage, the better it is. Most devices provide an option to enhance memory through add-on media cards. However, a device with in-built memory may offer faster response compared to the one using external storage.
Most navigation applications offer voice prompts for driving directions. The louder the phone speaker, the easier it is to follow the instructions. There is no easy measure to compare speaker quality, but phones with dual speakers offer better capability. It may be a good idea to try the speaker out before buying an expensive phone.