Coming soon Coming soon — Pentacomm and PentaPhone are in pilot and not yet generally available for purchase. Talk to us about early access
Pentacomm by Pentagon Business COM

The mobile endpoint of your business phone system Coming soon

PentaPhone

Company VoIP and mobile GSM, unified in one secure Android dialer.

PentaPhone turns every Android phone into a fully-fledged extension of the company phone system — the desk-phone feature set, standards-based push reachability, and encryption on every call, on the phones your employees already carry.

Executive summary

One dialer for the whole company

PentaPhone becomes the phone's default dialer, so company VoIP calls (SIP) and regular mobile (GSM) calls live in the same interface, the same call log, and the same contacts. Employees keep one device and one habit; the company gains desk-phone features, central control, and full call security on every handset.

PentaPhone is the mobile endpoint of the Pentacomm communications platform, built and supported by Pentagon Business COM. Because it speaks open telecom standards end to end, it also interoperates with any standards-compliant SIP infrastructure — no proprietary lock-in at the protocol layer.

Why it matters

What decision-makers get

  • One device, one number strategy — The office extension travels with the employee. Calls to the company number ring the mobile over data; outbound business calls present the company identity — lower mobile charges, consistent customer-facing numbers.
  • Reliable like a phone, not like an app — Standards-based push wake-up (RFC 8599) rings the phone even when the app is closed or the device is in deep sleep, with an automatic fallback where push is unavailable. Reachability is never silently lost.
  • Secure by default, not by option — Signalling runs exclusively over TLS and voice media over DTLS-SRTP; encryption cannot be switched off. Credentials live in hardware-backed encrypted storage, and private on-premises certificate authorities are supported.
  • Truly native Android integration — As a Telecom-framework default dialer, PentaPhone calls behave like ordinary phone calls: Bluetooth car kits, headsets, and wearables just work, and emergency numbers (112/911) always use the mobile network.
  • The desk-phone feature set, on mobile — Call waiting, swap, blind and attended transfer, voicemail with message-waiting indication, and a unified company call log.
  • Deployable and supportable at scale — Multi-account and dual-SIM aware, QR-code provisioning, automatic registration after reboot, live call-quality metrics, and one-tap redacted diagnostics for fast IT support.

Capabilities

Everything a business softphone needs

Each area below is shipped and production-ready today, in one application, with a guided first-run onboarding.

Unified calling

  • Outbound & inbound VoIP (SIP) over Wi-Fi or mobile data
  • Native GSM calling, dual-SIM aware, in the same dialer
  • Per-call line selection (SIP account / SIM 1 / SIM 2) with saved defaults
  • Full-screen incoming-call UI, including over the lock screen
  • Emergency numbers always forced onto the mobile network

In-call experience

  • Mute, hold/resume (both directions), in-call DTMF keypad
  • Audio routing: earpiece, speaker, wired headset, Bluetooth
  • HD voice with hardware echo cancellation & noise suppression
  • Calls survive network changes via automatic media re-negotiation
  • Proximity handling, call timer, live quality indicator

Business call control

  • Call waiting — second incoming call with automatic hold
  • Swap between two calls; add a second outbound call
  • Blind transfer and attended (consultative) transfer
  • Voicemail: message-waiting indication, one-tap dial, unread badges

Contacts & call history

  • Device address book integration — search, favorites, speed dial
  • Caller-name resolution on incoming calls and in the call log
  • Unified SIP + GSM call log, grouped by number, filterable per line
  • Missed-call notifications with unread badges

Administration & deployment

  • Multiple SIP accounts registered in parallel
  • QR-code and setup-link provisioning; guided onboarding
  • Automatic re-registration after reboot and app updates
  • Encrypted credential storage; certificate review & revocation
  • One-tap redacted diagnostic export for IT support

Quality & observability

  • Live in-call quality metrics: MOS score, jitter, packet loss
  • Per-call quality summary for troubleshooting
  • Privacy-scrubbed crash reporting, fully symbolicated
  • Always-on bounded local logging — zero start-up cost

What sets PentaPhone apart

Engineered for reliability, security, and trust

  • Registrar-integrated push wake-up — Incoming calls wake the phone through a high-priority push triggered by the SIP registrar itself (RFC 8599) — no third-party SIP push gateway sits in the call path. The phone rings from a closed app, deep sleep, or battery-optimized state, and falls back automatically to a battery-aware persistent connection on devices without push services.
  • No unencrypted mode exists — Signalling is SIP over secure WebSockets (TLS) only, and media encryption (DTLS-SRTP) is compiled in as mandatory. The product cannot be misconfigured into sending calls in the clear.
  • Private PKI, first-class — Ships with the Pentacomm root CA scoped to the app (it never touches the device trust store) and supports on-premises or self-signed server certificates through an explicit administrator approval flow with review and revocation.
  • A dialer, not an app pretending to be one — Deep Android Telecom integration means system-grade behaviour: lock-screen answering, Bluetooth and car-kit controls, correct audio focus, and emergency-call safety (112/911 always over the mobile network).
  • Controlled supply chain — The SIP protocol stack is developed in-house and the WebRTC media engine is built from audited source. No third-party SIP libraries sit in the call path, and quality, security, and support remain under one roof.
  • Privacy-respecting telemetry — Crash reports are scrubbed of personal data before leaving the device; diagnostic bundles are redacted and shared only by explicit user action. No advertising or analytics SDKs.
  • Continuously verified — The signalling stack is covered by an automated protocol test suite (golden traces from real platform traffic), and every release passes CI build, test, and lint gates before it ships.

The bottom line

One dialer. Every call encrypted. Reachable around the clock — on the phones your team already carries.

Transport architecture

Why WebSocket-only signalling

Most softphones still speak SIP over UDP — a transport designed for desk phones on a managed office LAN, not for devices that roam across corporate Wi-Fi, guest networks, hotels, and mobile data. PentaPhone deliberately ships a single signalling transport — SIP over secure WebSocket (RFC 7118) — and the difference shows up exactly where softphones traditionally fail:

Traditional SIP softphone (UDP / TCP / TLS) PentaPhone (SIP over WSS)
Restrictive networks UDP port 5060 is routinely blocked or throttled on corporate firewalls, hotel and guest Wi-Fi — calls simply fail. Signalling is indistinguishable from ordinary HTTPS and traverses any network where the web works — no firewall tickets.
Router "SIP ALG" Consumer and SMB routers rewrite SIP packets in flight — the classic cause of one-way audio and dropped registrations. TLS-encrypted WebSocket frames are opaque to middleboxes; there is nothing to inspect or mangle.
NAT traversal & inbound calls Incoming calls depend on fragile keepalive timers holding a router port binding open. One client-initiated connection; the server delivers every request — INVITE, BYE, CANCEL — back over it by construction (RFC 7118, RFC 5626).
Large SIP messages WebRTC-sized SDP bodies exceed the UDP packet limit, fragment, and get silently dropped. Stream transport — message size is a non-issue.
Encryption Optional and often left off; plaintext-UDP deployments remain common in the field. Always on — TLS is the only transport that exists in the product.
Device attack surface A listening SIP port is exposed to internet scanners — "ghost calls" and registration probes. No listening ports; the app only ever dials out.

The payoff

Calls connect on networks where traditional softphones fail — with no firewall tickets, no SIP-ALG battles, and no exposed ports.

Technical profile

Technical specifications

Platform Android 10 and newer (API level 29+), phones and tablets with telephony.
Application type Native Android application (Kotlin); registered system default dialer via the Android Telecom framework.
Signalling SIP over secure WebSocket (WSS) — TLS-encrypted, firewall- and NAT-friendly (standard HTTPS port model).
Media engine WebRTC, built from source and shipped with the app; per-call peer connections; concurrent-call capable.
Audio codecs Opus (preferred, wideband) · G.722 (HD) · G.711 A-law / µ-law — negotiated per call.
Audio processing 48 kHz pipeline with hardware acoustic echo cancellation and noise suppression.
Media security DTLS-SRTP key exchange + SRTP encryption, enforced — no unencrypted media path exists.
Authentication SIP digest, MD5 and SHA-256; credentials in hardware-backed encrypted storage.
Certificates Public CAs, bundled Pentacomm root CA (app-scoped), and administrator-approved private / self-signed CAs.
Incoming-call wake-up High-priority push per RFC 8599, triggered by the SIP registrar; automatic fallback to a persistent connection where push is unavailable.
Accounts Multiple SIP accounts in parallel + dual-SIM GSM; per-line outbound routing with saved defaults.
Provisioning QR-code scan and setup-link zero-touch flows; manual configuration; guided onboarding.
Emergency calling Emergency numbers always routed over the mobile network, never over VoIP.
Backend compatibility Pentacomm platform; any RFC-compliant SIP server with WebSocket transport and WebRTC-compatible media (DTLS-SRTP).
Diagnostics Live MOS / jitter / packet-loss metrics; per-call quality summaries; one-tap redacted diagnostic export; privacy-scrubbed crash reporting.
Releases Semantic-versioned, CI-gated builds; distributed via Google Play, with a managed internal channel for pilots.
Licensing Proprietary commercial software by Pentagon Business COM.

Product roadmap

Where PentaPhone is heading

The app evolves alongside the Pentacomm platform. The following capabilities are planned on the same standards-based foundation.

Planned

Conference calling

Three-way and multi-party audio conferencing from the in-call screen, built on the Pentacomm audio conference bridge.

Planned

Video calls

1:1 video calling — the shipped media engine already carries the full WebRTC video stack, secured by the same DTLS-SRTP edge.

Planned

Visual voicemail

Per-message voicemail list with in-app playback — and transcription, paired with the platform's voicemail-transcription module.

Planned

Company directory

A synchronized directory of colleagues and shared contacts served by the platform, merged into the Contacts tab with caller-name lookup.

Who it is for

Built for teams that live on the phone

  • Multi-site enterprises & hybrid teams — one extension per employee that works identically at the desk, at home, and on the road, with consistent policy and one call log.
  • Mobile-first workforces — field service, sales, and operations teams that need the company number with them, without carrying a second device.
  • Organizations replacing desk phones — keep the PBX feature set (transfer, hold, voicemail, call waiting) while retiring per-desk hardware.
  • Regulated and security-conscious organizations — every call encrypted end to end, credentials in hardware-backed storage, and support for a fully private PKI.

Put your phone system in every pocket.

See Pentacomm running on a live appliance and PentaPhone registered against it — or against your existing SIP platform. Talk to us about a proof-of-concept, licensing, and deployment.

Talk to us