Bring your PBX extension to your iPhone with UCM Phone, a SIP softphone designed for Grandstream UCM and compatible SIP PBX accounts.

Connect the extension supplied by your PBX administrator to make and receive audio calls through your existing phone system. UCM Phone uses the iPhone's system calling interface for incoming and outgoing calls.

CALL THROUGH YOUR PBX

• Dial extensions and phone numbers permitted by your PBX.

• Mute your microphone, put a call on hold, or switch between speaker and supported Bluetooth audio devices.

• Use the in-call keypad for voicemail menus and other systems that accept touch tones.

KEEP EVERYDAY TOOLS CLOSE

• View incoming, outgoing, and missed calls, with dates and connected-call durations.

• Tap a recent call to redial. The latest 200 call records are saved locally on your iPhone.

• Dial voicemail with a shortcut you can customize to match your PBX.

• Transfer a call directly or speak to the destination first with an attended transfer, when your PBX supports it.

• Enable Siri calling in Account to call a numeric extension, redial, or call voicemail by voice.

CONFIGURE YOUR EXTENSION

• Set your SIP server, port, extension, authentication ID, and optional outbound proxy.

• Choose UDP, TCP, or TLS transport, plus SRTP options to match your server.

• Enable Opus or G.711 audio codecs supported by your PBX.

• Store your SIP password in iPhone Keychain.

BEFORE YOU CONNECT

An existing SIP/PBX account and a reachable server are required. Your PBX administrator supplies the connection details, credentials, and calling permissions. Private PBX networks may require local Wi-Fi or a VPN. UCM Phone does not provide a phone number, PBX service, or calling plan.

Receiving incoming calls while the app is suspended or closed requires a compatible PBX or SBC push gateway and configured VoIP token registration. The app does not include a push gateway. Calling, voicemail, and transfer availability depend on your PBX and network configuration. This version supports audio calls only.

UCM Phone is an independent app and is not affiliated with or endorsed by Grandstream.

Privacy Policy

Last Updated: October 2026

This Privacy Policy explains how UCM Phone ("the app," "we," "us") handles information. UCM Phone is a SIP softphone that connects your iPhone to a phone system (PBX) that you or your organization operate, such as a Grandstream UCM.

Summary

• We do not operate servers that receive your calls, call history, contacts, or account credentials.

• We do not collect analytics, advertising identifiers, or tracking data, and we do not sell data.

• Information stays on your iPhone, except where it is sent to your PBX, your VPN provider, or a push-notification endpoint that you configure.

Information Stored on Your Device

• PBX account settings: server, port, transport, extension, authentication ID, outbound proxy, codec, and encryption (SRTP) options. These are saved in the app's local settings.

• Credentials: your SIP password, VPN credentials, the optional push-endpoint bearer credential, and the LDAP directory password. These are stored in the iPhone Keychain with the AfterFirstUnlockThisDeviceOnly protection level.

• Call history: the number, direction (incoming, outgoing, or missed), date, and duration of your most recent 200 calls.

• Directory results: names and extensions retrieved from your PBX's directory when you search. These are held in memory while the app runs and are not saved to disk.

• VPN settings: your VPN configuration, including any trusted Wi-Fi network names you add.

• Diagnostic log: error messages, registration status changes, and crash or hang notices, stored in the app's Application Support folder and limited to about 256 KB. This log is not sent anywhere automatically. It is shared only if you choose Share Diagnostics.

Information Sent and to Whom

• Your PBX: SIP signaling and call audio (optionally encrypted with SRTP), dialed numbers, DTMF tones, your extension and login, directory lookups, and voicemail and feature codes. The PBX is controlled by your phone system administrator, not by us.

• Your VPN provider: if you enable a VPN, traffic is sent to the IKEv2 or WireGuard server you configure.

• Your push-token endpoint: if you configure one, the app sends an HTTPS request containing a device identifier (a random ID generated by the app), your extension, SIP domain, Apple's VoIP push token, app bundle ID, and APNs environment. Your SIP password is never sent. This endpoint is operated by your phone system administrator or their provider, not by us.

• Apple: incoming-call notifications are delivered through Apple Push Notification service and PushKit. Call screens use Apple's CallKit, and Siri and CarPlay requests are handled by Apple. Crash and hang diagnostics are delivered by iOS to the app and stored locally, as described above. If you have enabled Share iPhone Analytics in iOS settings, Apple may share aggregated diagnostic data with us. That data is governed by Apple's privacy policy.

Information We Do Not Collect

We do not collect your name, email address, phone number, call content, contacts, or location. The app does not use location. It reads the name of the current Wi-Fi network only when you have granted Location access, and only to compare it with the trusted networks you have listed. The app includes no advertising or third-party analytics SDKs.

Permissions

• Microphone: to carry the audio of your calls.

• Local Network: to reach your PBX on your local network.

• Location (When In Use): only to read the Wi-Fi network name for trusted-network checks.

• Siri and CarPlay: to process voice and in-car call requests.

• Notifications and background activity: to ring for incoming calls.

You can change these permissions at any time in iOS Settings.

Your Choices

• You can delete call history and change or remove account, VPN, and push settings in the app.

• You can stop automatic VPN connection by tapping Disconnect in VPN settings.

• Deleting the app removes its local data from your device. iOS may keep Keychain entries, so clear saved credentials in the app before uninstalling if you want them removed.

• Requests about call recordings, logs, or directory data kept on your PBX should go to your phone system administrator.

Your Organization

If your organization operates the PBX, its own policies apply to calls, voicemail, recordings, and logs on its systems. We do not control those systems.

Children

UCM Phone is a business communications app and is not directed to children under 13. We do not knowingly collect information from children.

Security

Credentials are stored in the iPhone Keychain. Calls are encrypted only when your PBX and the app are configured for TLS and SRTP. No method of transmission or storage is completely secure.

Changes to This Policy

We may update this policy. Changes take effect when posted on this page, and the effective date will be updated.

Contact Us

If you have any questions about this Privacy Policy, please contact me.

Terms of Use

Last Updated: October 2026

These Terms of Use ("Terms") govern your use of UCM Phone ("the app"). By downloading or using the app, you agree to these Terms. If you do not agree, do not use the app. Apple's Standard End User License Agreement also applies to apps obtained from the App Store.

What the App Is

UCM Phone is a SIP softphone that lets you make and receive audio calls through an existing PBX account. The app does not provide a phone number, calling plan, PBX service, or telephone network. You need a PBX account, valid credentials, and a network path to your PBX, which your phone system administrator provides.

Authorized Use

You may use the app only with a PBX account you are authorized to use, and you must follow the rules your organization and the PBX operator set for calling, voicemail, and transfers. You are responsible for all activity under your account, and you must keep your credentials confidential.

Emergency Calls

UCM Phone is not a replacement for a traditional phone and may not support emergency calls. The app cannot reliably provide your location to emergency services. Calls can fail because of network conditions, VPN configuration, PBX settings, or device status. Do not rely on the app to contact emergency services such as 911 or 112. Use another phone in an emergency.

Network Quality and Third-Party Services

Call quality and availability depend on your network, your PBX, and any VPN you use. The app may connect to your PBX, a VPN provider, a push-notification endpoint, and Apple services such as CallKit, Siri, and CarPlay. We do not control these services and are not responsible for their availability or performance.

Acceptable Use

You agree not to:

• Use the app for any unlawful purpose or in violation of a PBX or carrier policy.

• Interfere with or disrupt any PBX, network, or service.

• Attempt to gain unauthorized access to any system, account, or communication.

• Use the app to harass, spam, or defraud anyone.

• Copy, modify, or reverse engineer the app, except where the law or an applicable open-source license allows it.

Open-Source and Third-Party Components

The app includes third-party software, including the Linphone SDK, which is licensed under the GNU AGPLv3 or a commercial license from Belledonne Communications, and WireGuardKit. Each component is subject to its own license. Links to licensing information are available in the app.

Trademarks and Affiliation

UCM Phone is an independent app. It is not affiliated with, sponsored by, or endorsed by Grandstream or any other PBX manufacturer. Grandstream, UCM, and other product names are trademarks of their respective owners and are used only to describe compatibility.

Disclaimer of Warranties

The app is provided "as is" and "as available," without warranties of any kind, express or implied, including merchantability, fitness for a particular purpose, and non-infringement. We do not warrant that the app will be uninterrupted, error-free, or compatible with every PBX.

Limitation of Liability

To the fullest extent permitted by law, we are not liable for any indirect, incidental, special, consequential, or punitive damages, or for any loss of data, profits, or calls, arising from your use of or inability to use the app. Our total liability for any claim is limited to the amount you paid for the app, or [USD $0] if you paid nothing.

Termination

You may stop using the app at any time by deleting it. We may stop offering the app or end these Terms at any time. Sections that by their nature should survive termination will do so.

Changes to These Terms

We may update these Terms. Continued use of the app after changes take effect means you accept the updated Terms. The effective date at the top of this page shows when they last changed.

Governing Law

These Terms are governed by the laws of the United States, without regard to conflict-of-law rules.

Contact Information

If you have questions regarding these Terms of Use, please contact me.