You can spot the zig-zag letters from their zig-zag lines. Let's look at the ‘V’ here. That down up movement makes the zig-zag. ‘W’ is the same, only with more diagonals. Down, up ...

Whether it's walking in a zig-zag motion as they stare down at their screens or inexplicably slowing down to take a call, mobile phone users and busy streets don't tend to mix. But the innovative ...