The unit conversion calculator with formulas of temperature(Fahrenheit/Celsius), speed(mile/kilometer), length(feet/inch/centimeter), weight(pound/kilogram/ounce), and volume(ounce/milliliter).

Make sure that third-party apps are allowed on your device: go to Menu->Settings->Security-> and check "Unknown Sources"

Tap the APK file. Allow the app any required permissions it asks for. Then, at the bottom of the installer window, click INSTALL.

You'll see a confirmation the app is installed. Now you'll see the app available in your list of installed apps.