– It saves SMS/MMS/Call Logs of secret contacts behind the calculator app. It also provides free messaging over the internet between two app users. It has some fantastic features like buy virtual phone numbers and SMS credits to send SMS.

– Platform: Android

– Technology: Android SDK, AIDL, java, sqlite, xml, json, REST API, xmpp, ML Kit, Google Drive, Google Play Service, Nexmo API

– App link: https://play.google.com/store/apps/details?id=com.privatesmsbox.calc