"*Windows Phone" . . . . . "*iPhone" . "Ringo"@en . . "*Android" . . . "Ringo is an international calling app for smartphones that utilizes dedicated phone circuits for making calls. Ringo uses local phone networks instead of the user\u2019s smart phone\u2019s internet connection to connect calls. Thus, the receiver is not required to download the app to receive a call.It is available in apps for Android, iOS and Windows Phone."@en .