Worried about leaky chats? Messaging apps are responding with security features

The popularity of messenger apps is fuelling plenty of innovation on how to keep private chats secure■ See more from the 20 innovations for 2015 seriesThanks to Facebook’s $19bn acquisition of WhatsApp in October, messaging apps are one of Silicon Valley’s hottest sectors – or biggest bubbles, if you’re a sceptic.A recent $62m funding round for Yik Yak, an app for chatting anonymously to people nearby that only launched in November 2013, can be seen as proof of either of those beliefs.