This is my current favorite app. Mounted on a Ram X Grip cell phone Mount on the left handle bar, I now have an accurate speedo in my glance distance instead of having to look down at the gas tank.
The Black rectangle is my phone case, shown because I was using the phone to take the picture.
The xgrip has 4 little rubber grippers that keep your phone in reach.
The Ulysses speedometer app also has a program launcher that let's me start Pandora or Waze or maps or whatever app I set up ahead of time in 2 clicks.
Also, multiple trip meters that store history, Max speed records, and alarms if I go over x mph. The dial turns red at 66mph, for example. .. and you can set those speeds.
One of the few apps I've paid for. $1.99 and also well worth it.