The Casio G-Shock GA-B2100-1A. Courtesy. In addition to Tough Solar, the new watches also offer a Bluetooth connection for even more features via a smartphone link; this doesn’t make it a full-blown ...

The Casio G-Shock DW-H5600 costs $299/£269 – so it’s a lot more than your average digital watch. ... With phone-connected GPS, you’ll always run into accuracy issues at points.