Secure Dialer

An open-source, privacy-first Android phone app built from scratch around one promise: zero internet permission, zero ads, zero trackers, and complete on-device privacy.

Features

Dialpad and outgoing calls

- Fast T9 predictive search from the dialpad by spelling names or dialing numbers. - Tactile haptic feedback and classic DTMF tones. - Smart clipboard paste that strips dashes, spaces, and formatting brackets. - Quick speed dial: long-press keys 1 to 9 to call favourites or emergency numbers. - Full dual-SIM support with a multi-SIM prompt on outgoing calls and customizable default SIM per contact or carrier.

Privacy and hardware security

- Zero internet access: the app does not declare android.permission.INTERNET, so it is physically impossible to send your data anywhere. - Custom call notes, speed dials, and blacklists stored locally with AES-256 SQLCipher encryption. - Encryption keys sealed inside the device hardware enclave (TEE or StrongBox) via Android KeyStore. - Encrypted backups with PBKDF2 and AES-GCM.

Everyday utilities

- Fake Call Simulator: trigger a realistic, customisable incoming call screen with a timer for politely excusing yourself. - In-call notes and a local recorder saved encrypted on device. - Motion gestures: flip face-down to silence incoming rings, or raise-to-ear to answer automatically. - Call back reminders scheduled as local alarms. - Visual call summary with offline statistics and charts.

Spam blocking and contacts

- Native call screening using Android's CallScreeningService, blocking unwanted callers, robocalls, and hidden numbers offline in under 5 milliseconds. - vCard and VCF backup and restore, completely offline. - Duplicate contact cleaner to find and merge repeating numbers.

Permissions

Secure Dialer requests only the standard telephony permissions required to be a default phone app. Since the app has no internet permission, all data stays on your device. This includes contacts read and write, call placement, call log read and write, audio routing, full-screen intent for incoming calls, notifications, SMS for quick replies, phone state for dual-SIM detection, and vibration for haptics.

License

GNU General Public License v3.0