A study of first dates discovered that couples that felt mutual romantic attraction subconsciously synchronised their heart rates (find it here) .

This could be the end of mixed messages. Bumble is the first app to use biometric data to let women know when a partner is truly interested. Users simply activate the Heartdate feature before they meet.

If heart rates synchronise, her watch will gently vibrate. With the tap of her finger, she can choose to share the good vibrations with her match. It’s the perfect chance to ask for a second date.