Good article in today's Wall Street Journal espousing 'peak smartphone' as handset makers' sales volumes wane with the market becoming saturated in developed economies, and some functions moving to other devices.
https://www.wsj.com/articles/the-big-hangup-why-the-future-is-not-just-your-phone-11547269202
Clearly smartphone manufacturers Apple, Samsung etc need the 'next big thing' to reinvigorate sales..