To be honest, it doesn't seem like Samsung cares too much about S Voice with no promotion on the website and that forces you to use it in any way. Samsung even has a press and hold of the physical home button launch Google Now with a double press launching the camera. In the past S Voice launched when you double pressed the home key.
Even though S Voice is not promoted, I figured I would test it out in direct comparison to Google Now to see if there were any major improvements or compelling reasons to use S Voice. There are not.
You can now setup S Voice to launch with a custom wake-up commend, recommended to be 3-5 syllables long. I followed the setup instructions and repeated the phrase four times. Just like the previous generation fingerprint scanner, I still haven't gotten the wake-up command to work once past the setup phase.
The voice wake-up will probably kill off your battery anyway, but since I could never get it to work I wasn't able to give it a real test. You supposedly can setup the wake-up command to launch when secured as well, with some limited functionality.
When you ask S Voice what you can say, you are given a list of 19 different examples. Small arrows can be tapped to see further examples of these commands. The commands include placing calls, sending messages, making appointments, posting to social networks, opening apps, setting alarms, searching the internet, controlling settings like Bluetooth, navigating, and more.
I went down the list and was able to perform all of these same functions with Google Now, except for having the news read aloud to me. I actually learned that you could control settings in Google Now, which I was unaware of until this test.
Google Now has much better voice quality, even with the downloaded voices in S Voice, and has the full Google Now cards experience that provides you with location and context based information.
Google Now can be setup for OK Google detection, unfortunately not with a custom phrase on the Galaxy S6. I have it setup for OK Google detection from the Google app and from any screen when the display is on or my phone is plugged in. Performance has been nearly flawless and I am using it more now than I ever was on other Android phones.
Google Now search results are more informative than S Voice, just take a look at my short screenshot gallery that shows some side-by-side results for common voice commands.
I was hoping that S Voice might have offered something amazing to match the design and camera of the S6 Edge, but that wasn't the case. I did learn more about the current version of Google Now and plan to use it extensively moving forward.
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