The Samsung Galaxy Note 4 variants which use Qualcomm’s Snapdragon 805 APQ8084 processors has the capabilities to always listen to your voice commands, even when your screen is off/locked. Samsung devices ship with the company’s own S Voice voice assistant app, but you can default that to Google Now which is a far better voice assistant than S Voice. This trick makes your Galaxy Note 4 to function in a similar way like the Moto X and its famous touchless control feature.

Oh and if you’re concerned about battery life, well, the Snapdragon 805 processor comes with a dedicated chip to reduce battery usage when the device is actively listening to users voice inputs. This is a similar setup like the last generations Moto X, only difference is you’re using the Google Now directly on your Note 4, whereas on the Moto X, Motorola uses its own customized interface but uses Google Now to process users voice commands. So it’s very much similar.

Follow the steps below to enable “Ok Google” always listening setup on your Note 4:

Open Google Search settings » select Voice » set language to “English (US)” and enable Audio history

└ “Ok Google” from any screen or lock screen seems to only work when you’ve selected (English US) as default language. Now select “Ok Google” detection from the same page and tick the checkbox next to “From any screen”, you’ll see Samsung’s S Voice pop up on your Note 4, just tap the mic button and train the app with “Ok Google” hotword.

└ It’s advised to do this in a quite room for best results. Once done training voice model, tick the “From lock screen” check box too (see screenshot below)

Turn off your phone’s screen now and say “Ok Google” to see it all in action. Enjoy! Also, if needed, setup S Voice to default to Google Now using the S for Voice app from Play Store

└ For help setting up the app, watch this YouTube video.

VIDEO INSTRUCTIONS

AFAIK, the always listening chip is included in Qualcomm’s Snapdragon 805 processor (APQ8084) only. Galaxy Note 4 variants running Exynos 5 processor may not be able to enjoy this feature. Below is a list of variants based on Snapdragon 805 processor.

List of Galaxy Note 4 variants using Qualcomm’s APQ8084 chipsets