I am having the same issue with my charge HR connecting to IOS 10.3.2 on my wife's iphone 6 wasnt able to get the device paired but then I used my Android Nexus 6P and immediately was able to pair the device and saw that the firmware needed to be updated which I did and then the Charge HR paired with the iPhone and began working normally. Hopefully the people having this issue have an Android phone as well as an iPhone!
Best Answer