These steps are helpful if you're following along with the Android instructions and saw some security warnings on Step 5.
Step 1: You may see the following message. Just click on settings to take you to "Security Settings" where you can allow the game to install.
Step 2: Click on "Unknown Sources" to allow Skillz apps to install on your device.
Step 3: Click "OK" to allow the installation. You can return here again to turn off the setting after the installation.
You can find the "Unknown Sources" setting in your "Settings" page under "Security."
Step 4: Then go to your "Downloads" area (found in your app menu) and you'll see the Skillz app as an "APK" file at the top of your recent downloads. Click on that file to install.