Car crashes are the top killer of teens in America, and a new study shows mobile phones are now involved in a quarter (26%) of all crashes in the US – an increase from 2013. With mobile phone bans failing, it seems the only solution to overconnected driving is more technology.

Car crashes are the cause of 1.27 million deaths a year, and technology companies are striving to drastically reduce this figure. Though Google's driverless cars are grabbing headlines, Cruise RP-1 is a hands-free driving system for normal cars, due for release in 2015.

Researchers have developed infrared software capable of understanding drivers’ facial expressions to identify signs of stress and fatigue. Car manufacturers want to create vehicles that ‘get to know their drivers’ and monitor their attention.

According to Motorola, people unlock their phones around 40 times each day. It takes them on average 2.3 seconds to do so, and as a result, half don’t bother to lock their phones at all. To remedy this, the brand is testing out temporary tattoos which unlock smartphones, no PIN required.