Cellcrypt Mobile for Android costs $1,500 per user per year. The software-only application is downloaded to an Android device. It uses Wi-Fi or an operator’s data channel on either GPRS, EDGE, 3G or satellite networks to transmit voice. Researchers have warned for years that voice traffic over cellular networks could be intercepted. The company already has voice encryption applications for Nokia E-Series and N-Series devices running Symbian S60s and BlackBerry devices.”]
Source: https://www.csoonline.com/article/2128832/cellcrypt-releases-voice-encryption-app-for-android.html