A SIP softphone that feels like the iPhone's own phone
SIPdia for iPhone and iPad rings on the system call screen, routes audio to AirPods, cars and headsets, and shares its settings format with the Mac app. For iOS and iPadOS 17 and later.
Download link coming with the releaseAll platforms
Shown with demo accounts and sample numbers.
- Status
- Release in preparation
- Requires
- iOS 17 / iPadOS 17 or later
- Architecture
- To be confirmed
- Package
- App Store
- Version
- Not released yet
What SIPdia does on iPhone and iPad
Checked against the current app. Premium features are marked.
Multiple SIP accounts
PremiumRegister several SIP accounts at once and pick which one each call goes out from.
Mac, iPhone and iPad
DetailsEncrypt SIP signaling with TLS and call audio with SRTP when your server supports them.
Mac, iPhone and iPad
DetailsCall recording
PremiumRecord a call to a WAV file stored on your own device.
Mac, iPhone and iPad
DetailsCall forwarding and Do Not Disturb
PremiumTurn forwarding and DND on or off at the PBX through feature codes, so they work when the app is closed.
Mac, iPhone and iPad
Save contacts with photos, favorites and notes. They sync to your Mac, iPhone and iPad, and calls and Recents show the caller's name and photo.
Mac, iPhone and iPad
DetailsSTUN and ICE
Work behind home and office routers with STUN and ICE.
Mac, iPhone and iPad
Opus and G.711 codecs
Opus for wideband audio, plus G.711 ulaw and alaw, the codec most PBXs and SIP providers support.
Mac, iPhone and iPad
CallKit integration
Incoming calls ring on the iPhone's system call screen, including the lock screen.
iPhone and iPad
Not yet: Push notifications for incoming calls
SIPdia must be open to receive calls. On iPhone the app unregisters about 20 seconds after leaving the foreground, so calls go to voicemail or forwarding. Missed-call notifications are shown locally.SIPdia on iPhone and iPad
Shown with demo accounts and sample numbers.
System call screen, real audio routes
- CallKit. Incoming SIP calls ring like cellular calls, on the lock screen too. Calls show in the status bar and Control Center, and the Phone app's Recents can list them.
- Audio routes. Earpiece, speaker, wired headsets, AirPods and other Bluetooth devices, and CarPlay.
- Contacts tab. Contacts with photos, synced with your Mac; Forwarding now sits on the Account tab.
- In-call controls: Mute, Keypad, Speaker, Audio, Hold, Add call, Transfer and Record.
- IPv4 and IPv6, with STUN and ICE for networks behind NAT.
- Keychain storage for SIP passwords on this device only.
How to connect a SIP account on iPhone
- Open SIPdia and sign in with Apple or Google.
- On the Account tab, enter the Server address (with
:portif needed), choose the Transport, and enter the Username and Password. On a PBX the username is the extension number. - Tap Add and Register. Allow the microphone, local network and notification prompts.
- To add another account, tap Add at the top of the Account tab. More than one account needs SIPdia Premium.
- Make a call from the Phone tab. Tapping the green button with no number redials the last number.
Full walkthrough: How to set up a SIP softphone on iPhone and iPad.
What happens when you leave the app
iOS suspends apps shortly after they leave the screen. A suspended app cannot keep a SIP registration alive or answer an INVITE. Apps that ring in the background rely on VoIP push notifications, which need a push server watching the SIP account. PBXs and SIP providers do not send those by themselves.
SIPdia therefore stays registered for about 20 seconds after you leave it, then unregisters its accounts. The server then follows its no-answer rule, typically voicemail or forwarding, instead of ringing a phone that cannot answer. Opening the app registers again. A call that is already ringing or connected keeps running in the background and on the lock screen.
Recommendation: set Forward when not answered to your mobile number or voicemail. Background calling through a push gateway is a planned next step, not a current feature.
Things to know
- TLS certificates must be valid for the server name and signed by a certificate authority in Mozilla's root list, which the app bundles. Certificates installed through configuration profiles are not used.
- Codecs: Opus, G.711 ulaw and alaw. No G.722 or G.729.
- The recordings folder is fixed to the app's Documents folder in Files.
- Not for emergency calls.
iPhone and iPad FAQ
Does SIPdia ring when my iPhone is locked?
Yes, while the app is open or a call is already in progress. Incoming calls use CallKit, so they appear on the system call screen, including the lock screen, and headset, Bluetooth and car buttons work.
Does SIPdia receive calls in the background?
Not yet. iOS suspends apps soon after they leave the screen, and a suspended app cannot receive SIP calls. SIPdia stays reachable for about 20 seconds after you leave it, then unregisters so the server can send calls to voicemail or forwarding. Push notifications for incoming calls need a push gateway and are not implemented.
Can I use AirPods, a car or a wired headset?
Yes. During a call the Audio button switches between the earpiece, the speaker, wired headsets, AirPods and other Bluetooth devices, and CarPlay audio.
Where are recordings saved on iPhone?
In Files > On My iPhone > SIPdia > Call Recordings. You can play and share them from the Recordings tab. Deleting the app deletes them.
Does it work on mobile data and IPv6-only networks?
SIPdia supports IPv4 and IPv6, which matters because many mobile networks are IPv6-only. Audio quality on mobile data depends on the connection; Opus copes with varying bandwidth better than G.711.
Do calls appear in the Phone app's Recents?
Yes by default, through CallKit, and you can call back from there. You can turn this off in SIPdia's settings.
Get SIPdia for your Mac, iPhone or iPad
Bring the SIP account you already have. The Mac and iPhone apps are in release preparation; download links appear on the download page when each release is live.