The global smartphone install base is set to grow 50 per cent in the next four years to 6 billion devices totaling US $355 billion in revenues, a new study claimed on Tuesday. Smartphones and tablets already account for more than 60 per cent of smart connected consumer devices, up from around 17 per cent in 2008, according to research firm IHS Markit. The smartphone install base was four billion in 2016, with the 6 billion figure expected to be hit in 2020, IHS Markit says. “Mobile innovations, new business models and mobile technologies are transforming every adjacent market as the mobile industry diversifies from the maturing smartphone market,” says Ian Fogg, director at IHS Technology. “Mobile devices and services are now the hub for people’s entertainment and business lives, as well as for communication. The smartphone has replaced the PC as the most important smart connected device.” Apple and Samsung currently lead the smartphone market and both are set to release new flagship devices this year. Alongside the growth in hardware, global consumer spending on mobile apps is set to reach US$74 billion by 2020 up from US$54 billion in 2016. Africa, the Middle East and Latin America will be the fastest-growing regions for spend on mobile apps, according to IHS Markit. “There are many opportunities for new apps, mobile payments and mobile money services. Asia, notably, will continue to play the number one role in the global apps market – accounting for more than 50 per cent of consumers spending,” IHS Markit said in its report. Two major services will grow on mobile – payments and messaging. The number of smartphones able to do device-based payment services will increase from 2.7 billion in 2016 to more than 5 billion by 2020, the report said. “This integration across their range of devices, apps, content and services will be crucial if they want to tap into the next waves of growth,” IHS Markit noted. Meanwhile, messaging apps such as WhatsApp will see their audience grow from more than 5 billion at the end of last year to 7.5 billion in 2020. Follow CNBC International on Twitter and Facebook .