However it should be noted that this is a different build number which is YNG1TAS17L where previously it was YNG1TAS0YL. This is to be expected since the newer build will come with the new feature, so even if you have updated your OnePlus One handset, you will need to download the update in order to gain the OK OnePlus feature.
For those unfamiliar, the OK OnePlus is a feature that the company had promised would be coming to OnePlus handsets way back in March of 2014. Basically it adds a voice command feature to the phone, kind of like Google Now, Siri, and Cortana. In fact the fact that it uses the “OK OnePlus” command alludes to Cyanogen’s plans to take Android away from Google, even their voice assistant feature.
The feature is also expected to allow users to unlock their phone using their voice, but they will have to go through a setup in order to get the phone to recognize and train their voice. The update is a little under 600MB so downloading it over WiFi might be a good idea.