Mobile Python: Rapid Prototyping of Applications on the Mobile Platform

6.4. GSM and GPS Positioning

Applications based on positioning are often claimed to be the most likely killer applications of the mobile platform. PyS60 gives you access to practically all public positioning techniques that are available for the current S60 mobile phones. As of 2007, the most typical positioning techniques are the following:

• external GPS over Bluetooth, as described in Section 7.5

• internal GPS, using the position module

• GSM cell IDs, using the location module

• SMS-based positioning using the messaging module. This service is provided by some mobile phone operators.

Besides these techniques, various positioning techniques based on WiFi or Bluetooth have been experimented with by research groups using PyS60 and custom extensions.

On S60 3rd Edition phones, access to both the internal GPS and GSM cell IDs are restricted by additional capabilities, which are not available for self-signed PyS60 – see Appendix A for more information. This means that if you have an S60 3rd Edition phone, you cannot use Example 49 with the self-signed PyS60 interpreter that we installed in Chapter 2. Instead, you need to obtain a personal, free, developer certificate from Symbian and sign the interpreter with it, as described in Section A.4.3. On S60 2nd Edition devices, no platform security is enforced and the GSM cell IDs can be accessed without trouble.

6.4.1. GSM Cell ID Mapper

We present a simple application that can be used to record positioning data and to retrieve your current location, ...