The advances in mobile telephony have been traced in successive "generations", starting with the early zeroth-generation (0G) services, such as Bell System's Mobile Telephone Service and its successor, the Improved Mobile Telephone Service.These 0G systems were not cellular, supported few simultaneous calls, and were very expensive.A feature phone has additional functions over and above a basic mobile phone which is only capable of voice calling and text messaging.Feature phones and basic mobile phones tend to use a proprietary, custom-designed software and user interface.Several other countries then followed in the early to mid-1980s.
Ten years later, in 2001, the third generation (3G) was launched in Japan by NTT Do Co Mo on the WCDMA standard.
Mobile phones offering only those capabilities are known as feature phones; mobile phones which offer greatly advanced computing capabilities are referred to as smartphones.
The first handheld mobile phone was demonstrated by John F.
Modern mobile telephone services use a cellular network architecture, and, therefore, mobile telephones are called cellular telephones or cell phones, in North America.
In addition to telephony, 2000s-era mobile phones support a variety of other services, such as text messaging, MMS, email, Internet access, short-range wireless communications (infrared, Bluetooth), business applications, video games, and digital photography.
Consequently, the industry began looking to data-optimized fourth-generation technologies, with the promise of speed improvements up to ten-fold over existing 3G technologies.