FeaturesiOS / Android compatibleBattery life: up to 6 hoursMicrophone / remote / volume controlSweat-resistant (IPX4)Active noise cancellationYour Nura NuraTrue Wireless Noise-Cancelling Earphones will begin by playing a range of tones into your ear and then measure a very faint sound, called Otoacoustic Emission (OAE), which your ear generates in response to these tones.  Encoded in the returning sound was is information about your hearing, and we synthesize this information with our self-learning engine to create your personalised hearing profile.NURATRUE can be used wirelessly via Bluetooth, which enables connection to a range of devices including mobile phones, tablets, computers and more.  NURATRUE measures your hearing automatically, delivering personalised sounds for you to use.  NURATRUE has in-built microphones that you can use for voice calls when connected via Bluetooth.