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Siperb Mobile Softphone

What Siperb Mobile Softphone is
Siperb Mobile Softphone puts an office phone extension on an iOS or Android device and connects it to an existing PBX or SIP system. The mobile app supports audio and video calls, attended and blind transfers, three-way conferencing, DTMF, call history, CDR, buddy presence, and end-to-end encryption using TLS and DTLS-SRTP. A proxy uses Apple APNs or Google FCM to wake the app and deliver calls while it is backgrounded, locked, or restarted. Mobile devices must use Proxy Registration Mode, which is also required for push notifications. The same Siperb account works across web, Windows, macOS, Linux, iOS, and Android, sharing call history, contacts, and settings. The free Personal plan has limited storage, seven-day SIP trace and registration activity logs, community support, and no technical support. Business costs £2 a month per domain user; Business Pro costs £5 a month per domain user.
Who it suits
Siperb suits end users who need a mobile extension connected to an existing PBX or SIP system, as well as IT administrators managing those connections. Developers and resellers can also use its separate embedding and co-branding resources.
What it does well
- Works with Asterisk, FreePBX, FreeSWITCH, and compatible SIP PBXs.
- Mobile app supports audio and video calls.
- Push notifications cover locked or backgrounded phones.
- Same account shares settings across six platforms.
- Free Personal plan is available.
What to know first
- Mobile devices require Proxy Registration Mode.
- Personal has limited storage.
- Personal includes no technical support.
- Siperb cloud components cannot be installed on customer servers.
Limits
Personal is free with limited storage, seven-day SIP Trace Logs, seven-day Register Activity Logs, community support, and no technical support. Business costs £2 per user per month and includes six-month logs; Business Pro costs £5 per user per month and includes logs for 12 months or more.
Plans
| Plan | Billed and limits | Price |
|---|---|---|
| Personal | limited storage · SIP trace logs 7 days · register activity logs 7 days · community support · no API access · no technical support | Free |
| Business | per month · SIP trace logs 6 months · register activity logs 6 months · API permanent token · technical support · internal domain users £0.50/user | £2 a month |
| Business Pro | per month · SIP trace logs 12+ months · register activity logs 12+ months · API permanent token · custom web hooks · custom navigation/pages · custom co-branding · internal domain users £0.50/user | £5 a month |
As siperb.com lists them, read 15 Oct 2026. The maker's own page has the final word.
Getting started
- Visit the Siperb mobile knowledge base at https://www.siperb.com/kb/mobile/.
- Choose Personal, Business, or Business Pro.
- Connect the service to a PBX or SIP system that can provision an extension.
- Use Proxy Registration Mode for the mobile device and push notifications.
- Install or access Siperb on iOS, Android, web, Windows, macOS, or Linux.
Siperb Mobile Softphone puts a PBX or SIP extension on an iOS or Android device, with companion clients for desktop and web. It is best for people and administrators who want mobile calling connected to an existing phone system. Broad PBX support and shared account data are strengths; mobile registration’s reliance on Siperb’s proxy is the key trade-off.
Overview
The mobile app works with Asterisk, FreePBX, FreeSWITCH and any SIP PBX that can provision an extension. Siperb’s proxy uses Apple APNs or Google FCM to wake the app and deliver calls when it is backgrounded, locked or restarted. That makes incoming calls more practical on a mobile device, but Proxy Registration Mode is the only mobile registration option, and it is required for push notifications.
For PBXs and ITSPs, Siperb supports outbound registration, outbound trunk and inbound registration connections. Web and desktop clients can also connect directly to a WebRTC-capable PBX through WebSocket Registration Mode, without Siperb in the call path. This gives mixed deployments more connection choices, although it does not remove the proxy requirement on mobile.
Key features
Mobile supports audio and video calls, attended and blind transfer, three-way conference, DTMF, call history, CDR and buddy presence. That covers routine extension use and common call-handling needs, rather than limiting the app to basic calling. The mobile feature set specifies end-to-end encryption using TLS and DTLS-SRTP, a meaningful safeguard for calls.
A single account works across web, Windows, macOS, Linux, iOS and Android, with call history, contacts and settings shared across platforms. That continuity suits users who move between desk and mobile clients. A documented REST API and permanent tokens for external backend systems also give administrators a route to integrate Siperb with their own services, though the product is positioned for end users and IT administrators rather than only developers.
Siperb provides separate developer embedding and reseller co-branding resources. Its cloud-hosted components cannot be installed on a customer’s own servers; organizations that require self-hosting should consider its open-source Browser Phone instead.
Pricing
The Personal plan is free. It has limited storage, seven days of SIP Trace Logs and Register Activity Log, community support and no technical support. That is a reasonable starting point for personal use or a small evaluation, but short log retention and the lack of technical help make it a weaker fit for teams that need operational support or longer troubleshooting history.
Business costs £2.00 per month per domain user, billed monthly, and extends both log types to six months with technical support. It is the practical step up for organizations that need help resolving technical issues or must retain logs beyond a week. Business Pro costs £5.00 per month per domain user, billed monthly, and extends both log types to 12+ months, also with technical support. It suits teams for whom longer log history justifies the higher per-user cost.
Free support covers general questions with an approximately 48-hour response; paid support covers technical issues with an approximately 24-hour response. Those response windows and the distinction between general and technical help matter when deciding whether Personal is adequate. The plans are billed per domain user, so the monthly total grows with the number of users.
Platforms
Siperb supports Android, iOS, Linux, macOS, web and Windows. Mobile and desktop apps and browser calling give users options across phones and computers, while shared contacts, settings and call history help preserve continuity between them.
Who it's for
Siperb is a strong fit for individuals and organizations that already have a SIP PBX and want its extensions on mobile as well as desktop or web. Administrators who value broad PBX compatibility, cross-platform account data, call-handling features and longer log retention on paid tiers have clear reasons to consider it.
It is less suitable for organizations that require mobile registration independent of Siperb’s proxy, or that need to install Siperb’s cloud components on their own servers. Personal users who depend on technical support or extended logs may also find the free plan too constrained.
Pros and cons
- Pros: Works with major named PBXs and other SIP systems that can provision an extension, giving existing deployments broad compatibility.
- Pros: Push delivery can wake the app when it is locked or backgrounded, addressing a central practical need for mobile calling.
- Pros: Shared history, contacts and settings across six platform types support switching between mobile, desktop and web clients.
- Pros: Paid tiers add technical support and extend both log types to six months or 12+ months, providing clearer operational coverage.
- Cons: Mobile has only Proxy Registration Mode, and push notifications require it; teams seeking a direct mobile-to-PBX registration option will need another fit.
- Cons: Personal limits log retention to seven days, offers only community support and excludes technical support.
- Cons: Cloud-hosted components cannot be self-hosted, which rules out Siperb itself for organizations with that deployment requirement.
Alternatives
Softphone and calling apps is a broader place to compare options. Blink is worth considering for a free softphone across Android, iOS, Linux, macOS, web and Windows; its free Linux, Mac and Windows downloads require a SIP account. Linphone is the alternative to consider when an open-source client that can be integrated under the GNU GPLv3 license is the priority, with proprietary licensing available for closed-source use.
SipPulse Softphone offers a free app plan for iOS, Android, Windows and Linux with unlimited users and installations, making it relevant when that stated user and installation allowance matters. Aria may suit personal, non-commercial use where unlimited calls, multi-account support and core softphone features are the draw of its free plan. Zoiper is another option for non-commercial use, with a free Windows, macOS and Linux plan limited to one account and two lines.
Bria Solo fits personal non-commercial users who can work within one device, one SIP/VoIP account and limited weekly calls on its free plan. MicroSIP is the narrower choice for a free Windows desktop SIP softphone under GPL v2. PortSIP Softphone may fit users seeking a free calling option in the Android, iOS or Windows platform range.
Verdict
Choose Siperb Mobile Softphone if you want to extend an existing SIP PBX to mobile while keeping call history, contacts and settings aligned across devices. Broad PBX compatibility, push delivery and a capable mobile call set make it a considered choice, with Business and Business Pro adding longer logs and technical support. Look elsewhere if mobile registration must bypass Siperb’s proxy or self-hosting is essential.
Verdict
Siperb Mobile Softphone combines PBX-connected mobile calling with shared account data across desktop and mobile platforms. Check the registration requirement for mobile devices and the support and log limits attached to the free Personal plan.
Questions
Is Siperb Mobile Softphone free?
Yes. Personal is free. Business costs £2 per user per month, and Business Pro costs £5 per user per month.
Which platforms does it support?
Siperb lists Android, iOS, Linux, macOS, web, and Windows. The mobile softphone runs on iOS and Android.
Which PBX systems can it connect to?
It works with Asterisk, FreePBX, FreeSWITCH, and any SIP PBX that can provision a SIP extension.
Does it support calls while the app is locked or in the background?
Yes. Siperb’s proxy uses Apple APNs or Google FCM to wake the app and deliver calls. Mobile devices use Proxy Registration Mode for this.
Does Siperb offer technical support?
Personal includes community support and no technical support. Business and Business Pro include technical support; free support covers general questions, while paid support covers technical issues.
Can Siperb's cloud components be self-hosted?
No. Siperb says its cloud-hosted components cannot be installed on customer servers; its open-source Browser Phone is the self-hosted alternative.
Facts from Siperb Mobile Softphone's own pages
- Android requirements
- Siperb’s download page lists Android 11 or newer and an approximately 65 MB AAB package. · siperb.com, 15 Oct 2026
- API
- Siperb exposes a REST API at api.siperb.com, with permanent-token authentication for external backends and versioned documentation. · siperb.com, 15 Oct 2026
- Audience
- Siperb positions the softphone for end users and IT administrators, while offering separate developer embedding and reseller co-branding resources. · siperb.com, 1 Oct 2026
- Audio and video
- The mobile client supports audio calls and video calls. · siperb.com, 15 Oct 2026
- Call records
- The mobile feature list includes call history and call-detail records. · siperb.com, 15 Oct 2026
- Call transfer
- The mobile feature set includes attended and blind transfer. · siperb.com, 15 Oct 2026
- Chrome extension limitation
- The Chrome listing says the phone must remain open to make or receive calls. · chromewebstore.google.com, 15 Oct 2026
- Company facts
- LinkedIn lists Siperb as privately held, founded in 2024, headquartered in London, with 2–10 employees. · linkedin.com, 15 Oct 2026
- Company identity
- The legal entity is SIPERB LTD, company number 15622824, shown as active at Companies House. · find-and-update.company-information.service.gov.uk, 15 Oct 2026
- Conferencing
- The app supports three-way conferencing. · siperb.com, 15 Oct 2026
- Connection methods
- Siperb supports outbound registration, outbound trunk and inbound registration connections to PBXs or ITSPs. · siperb.com, 1 Oct 2026
- Cross-platform account
- The same Siperb account works across web, Windows, macOS, Linux, iOS and Android with shared call history, contacts and settings. · siperb.com, 1 Oct 2026
- Developer SDK
- The product includes a Web Phone SDK with provisioning, embed and integration paths. · siperb.com, 15 Oct 2026
- Documentation
- The knowledge base covers end-user softphone setup, PBX connections, push notifications, API usage and developer embedding. · siperb.com, 15 Oct 2026
- DTMF
- DTMF is available for IVR navigation and similar tone-controlled systems. · siperb.com, 15 Oct 2026
- Encryption
- Siperb states that mobile media can use TLS and DTLS-SRTP end-to-end encryption. · siperb.com, 15 Oct 2026
- Headquarters
- Ruislip, United Kingdom · siperb.com, 28 Sept 2026
- iOS requirements
- Siperb’s download page lists iOS 18 or newer, iPadOS 18 or newer and visionOS 2 or newer for the mobile package. · siperb.com, 15 Oct 2026
- Messaging
- The Google Play listing states that the app supports instant messaging and file transfer. · play.google.com, 15 Oct 2026
- Mobile features
- Mobile supports audio and video calls, attended and blind transfer, three-way conference, DTMF, call history, CDR, buddy presence and end-to-end encryption. · siperb.com, 1 Oct 2026
- Mobile registration limit
- Proxy Registration Mode is the only registration option for mobile devices, and it is required for push notifications. · siperb.com, 1 Oct 2026
- Open-source licence
- SourceForge describes the open-source client UI as AGPL-3.0 licensed. · sourceforge.net, 15 Oct 2026
- Open-source scope
- The Browser Phone SDK and web-deployed code are open source, while the mobile apps and cloud service are proprietary. · siperb.com, 15 Oct 2026
- PBX compatibility
- The mobile service is documented for Asterisk, FreePBX, FreeSWITCH and other SIP-capable systems. · siperb.com, 15 Oct 2026
Where Siperb Mobile Softphone stands on Freedom251
- Softphone and calling apps#10 of 33
