GPS is a space-based global navigation satellite system(GNSS) that provides reliable location and time information in all weather and at all times and anywhere on or near the Earth when and where there is an unobstructed line of sight to four or more GPS satellites.It is maintained by the United States government and is freely accessible by anyone with a GPS receiver.

Push-to-talk(PTT)

Push-to-talk (PTT), also known as Press-to-Transmit, is a method of conversing on half-duplex communication lines, including two-way radio, using a momentary button to switch from voice reception mode to transmit mode.

WiFi

Wi-Fi is a trademark of the Wi-Fi Alliance,A Wi-Fi enabled device such as a personal computer,video game console,smartphone, or     digital  audio player can connect to the Internet when within range of a wireless network connectef to the Internet.

3GPP

The 3^rd Generation Partnership Project (3GPP) is collaboration between groups of telecommunications associations, to make a globally applicable third-generation (3G) mobile phone system specification.3GPP specifications are based on evolved Global System for Mobile Communications(GSM) specifications.

WiMAX

WiMAX(Worldwide Interoperability for Microwave Access) is a telecommunications protocol that provides fixed and mobile Internet access. The current WiMAX revision provides up to 40 Mbit/s.

SIM

A subscriber identity module or subcriber identification module(SIM) is an integrated circuit which securely stores the service-subscriber key(IMSI) used to identify a subscriber on mobile telephony devices.

OVI

Ovi by Nokia is the brand for Nokia's Internet services. The Ovi services can be used from a mobile device,computer(through Nokia Ovi Suite) or via the web(Ovi.com).Nokia focuses on five key service areas:Games,Maps,Media,Messaging and Music. Nokia's aim with Ovi is to include third party developers.