Sometime back I looked at 5 or so of these wrist style monitors and thought why buy one if you carry your smart phone? Being I always have my phone with me on bike rides, walking, hiking etc the Apps available are more than suitable and free. Now in fairness I am not going on this big health data tracking program either. Just basic steps and bicycling distance.
My current daily cycling avg is 8.2kms M -F and I always hit my 7500 steps goal.