Silent Phone is a mobile application for Android and iOS that provides end-to-end encrypted communications for enterprise and government use. It was originally the software powering the Blackphone hardware device, and is now available as a standalone app installable on any existing Android or iOS device. The app supports encrypted voice calls, video calls, conference calls, and group messaging. It also supports secure file transfers, including documents, videos, and images. Key operational features include burn timers that automatically redact messages after a set period, voice memos as a replacement for standard voicemail, and read/delivery receipts for messaging. The app supports zero-touch deployment, allowing administrators to roll it out across an organization without requiring manual configuration by end users. Silent Phone is used by businesses and government organizations. It does not require specialized hardware and can be deployed on standard consumer Android or iOS devices.