Compile and sign with Unity
File → Build Settings
Choose Android platform and press Player Settings button.
In player settings navigate to the android tab, and choose Other Setting menu.
To generate new key store check “Create New Keystore” toggle and press “Browse” button.
in the dialog box, select the path and name for the new keystore.
And press “Save” button.
Do not worry if Keystore file not yet created. Fill the Keystore password and Confirm Password fields.
Add new Alias and fill password for it
Fill all data in the dialog window and press “Create Key” button.
Keystore and Alias for signing your app is created.
Make sure to record the package name and signing certificate that you configured in this step. Using a different certificate or package name in your application will cause authentication failures.
Warning: Keep your private key secure. Before you run Keytool, make sure to read Securing Your Private Key for a discussion of how to keep your key secure and why doing so is critically important to you and to users. In particular, when you are generating your key, you should select strong passwords for both the Keystore and key.
Warning: Keep the Keystore file you generate with Keytool in a safe, secure place. You must use the same key to sign future versions of your application. If you republish your app with a new key, Google Play will consider it a new app. For more information on settings that must remain constant over the life of your app, see the Android Developer Blog post Things That Cannot Change.
Open a terminal, run the Keytool utility to get the SHA-1 fingerprint of the certificate.
keytool -exportcert -alias <alias-name> -keystore <path-to-keystore> -list -v
You will need this SHA-1 fingerprint to Generate an OAuth 2.0 client ID
You can build signed application now. Simply go to:
File → Build Settings, choose Android platform and press build button. Then upload and install produced apk on your device.
Or if you have your device connected to the computer with “USB Debugging” option. You can use File → Build and Run.