Easy Peasy
Earbux is a Progressive Web App (PWA) which means you dont have to download it from Playstore or Apple App store.
However it does require internet connection.
Simply follow the directions below to create a shortcut on your phone.

Android

Open Chrome. Navigate to Earbux.com. Tap the menu icon (3 dots in upper right-hand corner) and tap Add to home screen.

I-Phone

While viewing the website, tap in the menu bar.
Scroll down the list of options, then tap Add to Home Screen. If you dont see Add to Home Screen, you can add it.
Scroll down to the bottom of the list, tap Edit Actions, then tap Add to Home Screen.