Review: Polar M400 running watch review

Intro, battery, display and buildThe Polar M400 GPS running watch is now eight months old, and with its separate heart-rate chest strap, could be seen as a little 'first generation' by wearers of new-fangled, non-runner-friendly Apple Watches.However, don't be fooled - the M400 is one of the best pure running watches around, especially for the money (under £100, under $150, around AU£200). Though I reviewed it with a bundled Polar HR strap, which pushes it to more like £150/$230/AU$320 at cur