With the growth of telecom industry, the number of smartphone users has increased significantly and by 2020, there will be 6.1 billion smartphone users worldwide, says a survey. Conducted by leading Chinese language Internet search provider Baidu Inc, it said 60 per cent people use smartphones as a communication tool while 23 per cent use it as a companion. The remaining 8 per cent use it as a social media tool and 9 per cent people treat it as an entertainment device, according to the survey based on usage, trends and problems of smartphone users in 2015. Also read: One in 20 users to own smartwatch by 2020: Report The age group of 20 and below use their smartphones for music and entertainment, whereas the smartphone seems to be an inseparable companion for the age group of 20 to 29. In terms of number of apps installed, it said nearly 40 per cent of the users surveyed worldwide installed 21-50 apps on their phone. In Asia, 6 out of 100 people have 21-50 apps installed on their smartphones whereas 58 out of 100 people have less than 20 apps. Independent surveys conducted by DU Speed Booster and DU Battery Saver apps, owned by Baidu, says that battery-related overheating issues are particularly prominent among users across the globe. Also read: India beats US to become second largest smartphone market: Report Overheating is a result of too many apps running in the background, consuming RAM and CPU resources, frequent web access attempts, causing excessive CPU usage and large cache files accumulated which impacts speed. Speed related issues can be handled by de-cluttering RAM which can result in a 60 per cent speed improvement, it added.