You can find free caller tunes for your smartphone by downloading and installing the Zedge app. This app is free for Android, Apple and Windows phone users. You can then search Zedge for the ringtone you want to add to your smartphone.
The Zedge app is available to download free of charge from the Google Play Store, Apple App Store or Windows Phone store. It features 8.4 million free downloads to choose from with the downloads divided into 27 different categories. Zedge also allows you to download free wallpapers and themes for your smartphone. You can use Zedge by creating an account on its website.