While every Android phone offers Google Now for voice commands, Samsung and Motorola offer something extra. Moto Voice extends Google Now voice commands to every part of the phone, even when the screen isn't on, and allows users to issue an impressive array of additional commands. S Voice, on the other hand, largely replaces Google Now with its own set of tools for answering questions and acting as a virtual assistant.
Both solutions require you to have specific hardware in order to enjoy the experiences offered, and both services are arguable better than standalone Google Now for voice commands, but which offering has the accuracy and feature set that allows the service to stand out in the crowd?
Hotword setup and detection
The most important part of any voice system is the ability to get the service to start. While Google is perfectly content to have you repeat "OK Google" until you're muttering it in your sleep, Samsung and Motorola allow you to define your own hotword. Since I'm a great big nerd and I recognize the importance of having your hotword be something mildly complex in order to increase the chances of detection, I set both S Voice and Moto Voice to "Computer, respond" in their respective settings.
Both S Voice and Moto Voice use a three-step recording process to capture your hotword. You repeat it three times into the phone, and after you see a confirmation screen you can use that hotword whenever you want. Motorola's approach here feels a little more focused, offering an ambient volume page if it is too loud in an environment to record your hotword, but the end results were the same.
Motorola's voice detection is still largely without equal.
With the screen on, Motorola and Samsung both respond well to the hotword. In testing the 2014 Moto X and the Galaxy S6 side by side, Motorola caught the word and responded all ten times, while Samsung missed once on the sixth test. Motorola also routinely responded faster than Samsung, with Moto voice springing to life almost instantly while S Voice took nearly three seconds to start listening in most cases. Motorola and Samsung both offer the ability to detect hotwords when the screen is off, but in our testing S Voice was noticeably less reliable without the screen on. Additionally, if you have security enabled on your lockscreen — even the fingerprint sensor — S Voice won't complete any actions until you unlock the device. Motorola, on the other hand, will allow you to bypass the lock screen for most activities if you allow it.
Motorola's voice detection is still largely without equal. While Samsung has made some impressive strides in their detection methods in S Voice, it clearly lags behind the constantly improving Moto Voice.
Availability and execution of commands
You've now gotten your smartphone to recognize your existence and acknowledge you as a creature worthy of accepting commands from. Now what? Moto Voice leans heavily on Google Now for a lot of things, but also includes a number of important commands that are exclusive to this platform. S Voice, on the other hand, is a complete replacement of Google Now for everything but search, which includes a nice minimalist UI that doesn't pull you away from whatever app you are in to complete a task with pop-up cards for results and confirmation.
S Voice would be a clear winner here if Samsung could figure out how to play nice with Google Now.
Moto Voice and S Voice cover the basics fairly well. You can get the weather, send a message to someone in your contacts, take a picture, play music, launch apps, and the list truly does go on and on. There's a few critical differences, however, and these differences can make a huge difference depending on what kind of user you are. Moto Voice tends to stumble when asked human language math questions like "How many hours are there until 2PM?" while S Voice leans on Wolfram Alpha to give you the answer in hours, minutes, and seconds respectively. S Voice stumbles on continued listening prompts like "What song is this?" and seems incapable of delivering an answer to a question that is based on an answer provided by a previous inquiry. S Voice is also incapable of telling you where your phone is when lost, which is something Motorola has been doing well for quite a while due to the ability to listen when the screen is off.
While S Voice is slower to respond to initial voice detection, the way Moto Voice hands off the command to Google Now makes the execution of a command take longer. There's no clear winner between the two when it comes to executing a command, as both services are missing what could be considered critical functions, but S Voice would be a clear winner here if Samsung could figure out how to play nice with Google Now.
Motorola wins by the slightest of margins
The truth is, after using both services side by side for a couple of days, there isn't a clear winner. Samsung's UI for S Voice is superior to Moto Voice in just about every scenario, but the screen needs to be on to function and it's missing some fairly common commands. On the other hand, it is deeply frustrating to wait for Moto Voice hand a command off to Google Now only to see it fail because the service can't do fairly basic math in human language form. I'm also not the biggest fan of the way Google Now tries to take my voice searches and make them contextually relevant days later, which is something I never have to worry about with S Voice.
Neither service is perfect, but both have the potential to grow and improve at a healthy rate. S Voice on the S6 is vastly improved over S Voice on the S5, and since Moto Voice is a Play Store app Motorola can push updates as they please — and they do. That, and the ability to function properly when the screen is off, make Moto Voice the better service for now, understanding fully that it's a narrow victory that Samsung could easily fix in the next software update. Here's hoping they do, and soon.