Recently it was announced that Google Play now carries a Google's "calculator" app which includes android wear support (you can pull up calculator app on your wrist and do simple calculations there). If you have a nexus device, you already have the Google calculator app and may have noticed the update appear. I'm usually a fan of Google apps over 3rd party apps. But in this case I have to say that I prefer a 3rd party app: "Calculator for Android Wear" by Wearable Software (WS). There are three reasons: WS's app displays all the digits, simple operators (+,-,x,/) along with decimal point and "=" on the main screen (see image here). So you can do these arithmetic calculations all from the main screen. In contrast, Google's app only displays the digits along with "=", but you have to tap to get to an overflow screen that houses the operators +,-,x,/ (see main screen here and overflow screen here). It's pretty obvious with the google setup there's not a single calculation you can do without going to the overflow screen. Google's intent was obviously to make the buttons bigger, but for me it's not necessary... If I place my 3/4 fingers on my wrist to the right of my watch, I can steady my hands and easily pivot my 2nd finger (pointer finger) to tap exactly where I want on the watchface... I have no problems or slowdown using the smaller WS buttons on my moto360. The google interface (operators moved to overflow to increase number button size) only creates unnecessary extra taps and complexity for me. WS's app has an overflow screen as well (see here), but it houses a whole bunch of additional functions that aren't even available anywhere on Google's app (square-root, sin, cos, tan, ln, exponentiation). WS's app has a mic option on the main screen which takes you directly to google where you can say your calculation and result is seamlessly delivered back to the result area of the calculator where you can work with it further if you choose. Google doesn't have that integration built into their calc app. I realize we can of course get to google voice commands other ways (ok google) but I think it's a nice touch to have it available right in the calc app. I realize most people don't see a huge need for calcuator apps on their wrist. Personally, I usually do quick easy/approximate calculations in my head and more complicated/exact calculations on the phone/computer. I think it's sometimes helpful to have another quick/easy option (the watch) in the middle between those other options. Sometimes I use watch to double check my mental calculation after I realize that I am not 100% confident in the answer I just gave. You may or may not have need for a calculator app on your wrist, but if you do, then you might as well use the one "better" one (imo).