I used L'Oréal's tiny wearable to keep me safe in a heatwave

It's hot. Like, real hot. For those reading this who aren't in the UK, we're experiencing a massive heatwave. Temperatures have already hit 33 degrees centigrade (91 degrees Fahrenheit) - which is significant, for us. It's been prime shorts and shades weather for a few weeks now, so I took it as the perfect opportunity…