There are two ways to install WordPress Mobile Pack: (1) Install from your WordPress Admin Panel (2) Install from the WordPress Plugin Directory
1. Install from your WordPress Admin Panel
From your WordPress Admin Panel navigate to Plugins > Add new, and search for "WordPress Mobile Pack". Click the Install Now button and once the plugin has been installed, click Activate Plugin.
2. Install from the WordPress Plugin Directory
Once on the WordPress Plugin directory click the Download button to get the .zip file, then go to your WordPress Admin Panel > Plugins > Add new , click Upload Plugin and upload the .zip file. Remember to activate the plugin after installing it.
Accessing the Progressive Web App
Once the plugin has been installed and activated, a new "WP Mobile Pack" menu item should appear on the left. Click on it to visit the "WordPress Mobile Pack Admin" page. WordPress Mobile Pack FREE comes with a default mobile app theme called "OBLIQ".
You'll be able to access it by simply navigating to http://www.yourdomain.com from your mobile device or simply use Chrome DevTools' Device Mode to simulate a wide range of devices and how the progressive web application behaves.