Mio offers its Mio Fuse Heart Rate, Sleep, and Activity Tracker in Crimson, Cobalt, or Aqua, model no. 59P, for $129. Coupon code "SAVE25" drops the price to $96.75. With free shipping and excluding the below mention, that's the lowest total price we could find by $6, although most retailers charge $129 or more. Compatible with iOS and Android, it tracks sleep, steps, calories, distance, pace, and goal progress. The tracker is waterproof to 100 feet and features an optical heart rate sensor, 3-axis accelerometer, Bluetooth 4.0, and watch function. It's available in sizes regular and large, although not in all size/color combinations.
A close price: Target has it in Cobalt for $99.99 with free shipping. It's available in size S/M only.