Bose Hear App's CustomTune Technology pairs with Bose SoundControl Hearing Aids to provide clinically-proven, audiologist quality customization. With just two controls, you can set the volume and sound clarity to your liking. World Volume turns up the sounds around you so you can hear better, while the treble/bass settings let you adjust the tone so voices and sounds are clearer. Note: This app also pairs with Bose Hearphones. This app is NOT compatible with other Bose Headphones, such as the Bose Noise Cancelling Headphones 700, QuietComfort Earbuds, Sport Earbuds, or Sport Open Earbuds. California Privacy Notice of Collection : https://www.bose.com/en_us/legal/california_privacy_notice_of_collection.html