It was widely expected that the Nexus 5 from Google would also include the always on listening feature as seen on the Moto X, since the Snapdragon S800 processor has a dedicated core for audio processing while barely sipping any power. While the Nexus 5 does have the ‘Ok, Google’ feature, it only works on the home screen, and not when the device screen is turned off.

As it turns out, there is more to Motorola’s Touchless control feature than what meets the eye. 

Siggi Simonarson, a software engineer, was pretty frustrated with the lack of always on voice detection feature on his Nexus 5. He decided to tear up the APK of the Touchless control app on the Moto X to see if he could get it to run on the Nexus 5. It turns out that Motorola is using Nuance’s Dragon Speech Recognition Software to perform some part of the voice recognition on the Moto X. The ‘Ok, Google’ hot word detection, even when the device is locked or while using an app, being a part of it.

Nuance is a leading provider of speech and imaging solutions, and is also the creator of Siri as seen on Apple’s iOS devices. The Galaxy Note 3 from Samsung also has an always-on listening mode, similar to the Moto X, for S-Voice and the software recognition once again has been provided by Nuance.

It is very much possible that Nuance has a patent on this feature, which meant that Google might have had to pay the company royalties for every Nexus 5 that was sold, if it included this feature. Considering the low prices of the Nexus 5, chances are we might never see this feature make it to the Nexus devices, since Google is not really interested in using a third party voice recognition feature.

Hopefully, down the line, Google manages to find a workaround to this patent and brings a similar feature to the Nexus devices.