X16 Fitness Tracker Bluetooth Smart Bracelet for iOS / Android Smart Phone, Heart Rate / Anti-lost worth to buy? Thanks for it if those of you who have purchased X16 Fitness Tracker Bluetooth Smart Bracelet for iOS / Android Smart Phone, Heart Rate / Anti-lost could share about what you think of the product. I would love any extra info, as it is quite pricey as $33.00 and I just want to know it is good before paying for it.