Introducing SIPdia: A SIP Softphone for Mac, iPhone and iPad

SIPdia is a SIP softphone for macOS, iOS and iPadOS. It connects to a PBX or a SIP provider using the standard protocols, places and receives calls, and stays out of the way. This post explains what the app is, what it does today, how the free and Premium plans divide, what is not there yet, and where the release stands. Everything below describes the current state of the app; nothing is a promise about future versions.

What is SIPdia?

A softphone is an app that behaves like a desk phone. You enter the server address, username and password from your PBX or provider, the app registers, and from then on you make and receive calls on your computer or phone. SIPdia does exactly that for Apple devices.

The call engine is baresip with libre, with Opus for audio coding and OpenSSL for encryption. These are open source components; the app around them is built with SwiftUI for each platform. SIPdia is made by SpaGreen Creative. One bundle ID is shared between the Mac and iPhone/iPad apps, so a purchase on one covers the others on the same Apple Account.

Which platforms?

• macOS 14 and later. Universal build for Apple silicon and Intel Macs. Sandboxed. Planned distribution is a notarized build or the Mac App Store.
• iOS and iPadOS 17 and later.

There is no Windows, Linux or Android app. The platform pages for those systems on this site exist to say so clearly and to point to the protocol guides, which apply to any softphone.

What does it do?

Accounts and transport

• Multiple SIP accounts, all registered at the same time, with a From picker when dialing.
• SIP over UDP, TCP or TLS. DNS SRV lookup when no port is given.
• Separate SIP domain, outbound proxy and auth username in the Advanced section.
• STUN and ICE for NAT traversal. IPv4 and IPv6 on iOS.
• SIP password stored in the Apple Keychain.

Audio and encryption

• Codecs: Opus, G.711 ulaw (PCMU) and G.711 alaw (PCMA). No G.722 and no G.729.
• SRTP media encryption with an Encrypt audio setting of Off, Optional or Required.
• TLS requires a certificate from a public certificate authority. Self-signed certificates are rejected.
• Echo cancellation and noise reduction through Apple's voice processing.
• DTMF as RFC 2833 RTP events.

Calls

• Make and receive calls, hang up, mute, hold and resume, keypad tones.
• Several calls at once, with switching between them.
• Blind transfer, and attended transfer between two open calls.
• Recents with call history, missed-call local notifications, and a voicemail button.

Platform integration

On the Mac: a floating incoming-call window that appears on every Space, a menu bar icon, the app keeps running when the window is closed, selectable microphone, speaker and ring devices, open at login, and keyboard shortcuts for answer, hang up, mute, hold and record.

On iPhone and iPad: CallKit, so incoming calls appear on the system call screen and lock screen while the app is open, optional integration with the Phone app's Recents, headset, Bluetooth and car button support, CarPlay audio, and audio routing to earpiece, speaker, wired headphones, AirPods and Bluetooth devices.

Privacy and account

Sign-in with Apple or Google is required, through Firebase Authentication, and the account can be deleted from inside the app. There are no analytics, ads or tracking in the apps. A detailed logs setting records SIP messages and offers Show and Share Logs for troubleshooting.

What is free and what is Premium?

SIPdia is free to use with one SIP account. The free plan includes calling, hold, transfer, TLS and SRTP, STUN and ICE, Recents, the voicemail button, and contacts with photos, favorites and notes, synced across your Mac, iPhone and iPad through your SIPdia account, so incoming calls and Recents show the caller's name and photo. Encryption is not held back.

SIPdia Premium adds:

• More than one SIP account.
• Local call recording to WAV. Each call can be recorded once. On the Mac the default folder is ~/Music/Call Recordings; on iOS recordings are under Files > On My iPhone > SIPdia > Call Recordings. A notice before recording states that the other party is not told.
• Call forwarding (all, busy, no answer) and Do Not Disturb, implemented through PBX feature codes with editable defaults.
• Importing and exporting contacts: from the Contacts app, vCard or CSV in; vCard or CSV out.

Premium is an Apple in-app purchase. One purchase covers iPhone, iPad and Mac on the same Apple Account. Plan options and terms are on the pricing page; this post does not list prices.

What is not there yet?

Being clear about gaps saves everyone time.

• Push notifications for incoming calls. Not implemented. On iOS the app must be open and it unregisters about 20 seconds after leaving the foreground. On macOS the app must be running and a sleeping Mac misses calls. Only missed-call local notifications exist. VoIP push with a push gateway is the planned next step.
• Windows, Linux and Android. No apps for these platforms.
• Self-signed TLS certificates. Rejected. Use a public-CA certificate, or UDP or TCP over a VPN.
• Video calls, messaging, presence or BLF, provisioning, central administration, SSO, team billing. None of these are present.
• Emergency calls. Not reliable. Whether an emergency call connects depends on the SIP provider, and the app cannot share location.

Where does the release stand?

Both apps are at version 1.0 and are in preparation. There is no public download link and no store listing yet. The download page will carry links when they exist; until then it explains the platform requirements. Nothing on this site should be read as a release date.

Who is it for?

SIPdia suits people who have a SIP account from a PBX or a provider and want a native app on a Mac, iPhone or iPad. It works well with Asterisk-based systems such as Issabel and FreePBX and with standards-based SIP trunks. The integrations section covers the settings for each.

It is less suitable, at the moment, for anyone who needs the phone to ring while the app is closed, who needs video or chat, or who works on Windows, Linux or Android.

Next steps

Check the platform requirements on the download page, browse the features, and read the security page for how TLS and SRTP are handled. If you are setting up a PBX, the guides and troubleshooting sections cover the protocol side in detail.