Works great! Since there is the Android app is that synchronize a breeze and you do not have to pay extra to the PC. Big minus: For women wrists the size of the clock and especially the wide and long strap is oversized. Therefore, it sucks the huge device ever to wear the arm because it simply disturbs and difficult to be worn under clothing with long sleeves. Here Polar should lean on the Watch RCX3 from own house in white. The tape of RCX3 is beautiful narrow and also much softer and more supple than the M400.