LTE will remain the dominant mobile service for several years to come, according to the latest forecasts from the GSMA at Mobile World Congress. Its ‘Mobile Economy’ report predicts that 4G will grow to 53 percent of the world's mobile connections by 2025 from 29 percent in 2017. While the first 5G networks are expected to launch late this year, the new service will be used by only 14 percent of mobile lines in 2025, according Telecompaper. Just under a decade since the first commercial 4G networks were launched, 4G is on track to become the world’s leading mobile network technology by next year, according to the report. 5G connections are forecast to reach 1.2 billion by 2025, accounting for 14 percent of the total connections at that time.
In total, the GSMA predicts the number of mobile connections in the world, excluding cellular IoT, to grow to over 9 billion in 2025, of which 77 percent will use smartphones. The number of unique subscribers will be a lower 5.9 billion, equal to 71 percent penetration of the world's population, up from 5.0 billion or 69 percent in 2017. That's equal to a 2.1 percent CAGR for subscribers over the five-year period. Mobile internet users are predicted to grow at a faster rate of 5.3 percent over the period, to reach 5.0 billion in 2025. 
IoT connections will be the fastest growth market, tripling to an estimated 25.1 billion connections in 2025 over cellular and other wireless networks, from 7.5 billion in 2017. 
The industry group's report also looks at the mobile ecosystems contribution to the economy. It's estimated to account for 4.5 percent of global GDP in 2017, a contribution equivalent to USD 3.6 trillion in economic value added. This contribution is forecast to reach USD 4.6 trillion, or 5 percent of GDP, by 2022, thanks to the growing take-up of mobile services and M2M/IoT. 
Mobile operator revenues are forecast to grow slightly in the period, from an estimated USD 1.05 trillion in 2017 to USD 1.10 trillion in 2025. Capital expenditure in the period 2018-2020 is estimated at USD 497 billion.