Your iDevices (and your MAC, when Yosemite is released in about a month) are 'aware' of each other when in proximity and on the same Wi-Fi network. If anyone know how that works, please let me know.'
You asked: ' I noticed iPad has a new feature with iOS 8 called Handoff which will allow you to use your hearing aids with any iOS device that is on the same wifi network and iCloud account without having to pair up to the hearing aids.