A88+ bluetooth 4.0 Smart Watch Heart Rate Monitor Blood Oxygen Monitor For iOS iPhone Android worth to buy? Thanks for it if those of you who have purchased A88+ bluetooth 4.0 Smart Watch Heart Rate Monitor Blood Oxygen Monitor For iOS iPhone Android could share about what you think of the product. I would love any extra info, as it is quite pricey as $57.68 and I just want to know it is good before paying for it.