0G Phones The basis of modern mobile phones is the celular concept. Prior to this there were many radio telephones using the PTT (Push To Talk technology). This used the whole of the available spectrum to connect one phone so the technology is unable to scale to the level needed for the modern mobile phone user. Hence a different model for mobile phone networks was needed.

1G Phones The first mobile phones were based on analogue technology. These phones were based on circuit switching, so still used a dedicated frequency, thus still a capacity issue. The cellular concept allowed for many cells sharing the same frequencies, and as these cells are small, a larger overall phone capacity is possible. The only function of these phones was to make phone calls; the ability to move around when speaking was novel. Phones of this generation were large and heavy, mainly caused by the battery size.

2G Phones A switch to digital technology allowed for digital communications with more sharing of the frequency and greater capacity. These phones also provided SMS messages and a (slow) access to the Internet. Typical phones of this era are the Nokia 7110 which was the first to provide Internet access. Initial Internet access was by way of dial-up connection but later with GPRS always-on technology the modern way to access the Internet was available. Later EDGE technology speeded up the network connections.

3G Phones The search for speed began with 3G mobile phone technology. The demand for services based on the Internet led to a demand for capacity and speed on the network. The basic 3G networks were based on UTMS technology operating at 800MHz and 2.1GHz. This added capacity allowed for video and even 3GTV experiments. Typical phones of this era was the Nokia N95. Later developments for the 3G network was the speed up provided by HSPA software upgrade.

4G Phones Again a new network with the drive for speed and capacity. A fully data-based model showing the focus on data on the Internet. The technology used is LTE, Long Term Evolution, providing for incremental development. The proposed implementation for SMS and Phone calls is via data-driven apps; Internet messaging and VOIP phone calls. Currently these services can be swapped to the GSM network. Recent development of 4G is towards LTE Advance labelled as 4G+.

5G PhonesThe initial implementations of the 5G network are a further evolution from 4G, more speed and capacity provided by various technical enhancements. Later implementation of mmWave 5G will be a significant change. The evolution simplifies the core network bringing much to the periphery and within the cloud. Massive MIMO provides the extra speed. Currently (July 2019) there is controversy in the use of Huawei and other Chinese equipment in the 5G networks in the UK. The only non-Chinese 5G phone available now is the Samsung Galaxy S10 5G.