1. GPS
2. Differentiate SMS and MMS:
a. Short Message Service(SMS):
It allows transferring short text messages containing up to 160 characters between mobile phones. The sent message reaches a Short Message Service Center(SMSC), that allows ‘store and forward’ systems. It uses the protocol SS7(Signaling System No7). The first SMS message ‘Merry Christmas’ was sent on 03/ 12/1992 from a PC to a mobile phone on the Vodafone GSM network in UK.
b. Multimedia Messaging Service (MMS):
It allows sending Multi-Media(text, picture, audio and video le) content using mobile phones. It is an extension of SMS.