Media playback is unsupported on your device

What price for free wi-fi?

28 July 2014 Last updated at 11:25 BST

Smartphone users are always looking for free wi-fi but at what price does it come? Businesses are looking at ways to make the free wi-fi they offer work for them too. It can track our movements through our phones and reveal a great deal about us to those who have something to sell.

BBC Click's Spencer Kelly reports.

Watch more clips on the Click website. If you are in the UK you can watch the whole programme on BBC iPlayer.

BBC © 2014 The BBC is not responsible for the content of external sites. Read more.

This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.