Siperb Mobile Softphone

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 conferences, DTMF, call history, CDR, and buddy presence. Listed encryption uses TLS and DTLS-SRTP. Siperb’s proxy uses Apple APNs or Google FCM to wake the app and deliver calls when it is in the background, locked, or restarted. Mobile devices use Proxy Registration Mode, which is also required for push notifications. The service works with Asterisk, FreePBX, FreeSWITCH, and SIP PBXs able to provision an extension. The same 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. Free support covers general questions, while paid support covers technical issues.

Siperb Mobile combines mobile calling with shared account details across desktop and web clients. Its mobile registration requirement and Personal plan’s support limits are important distinctions.

It suits end users who want a mobile extension connected to an existing PBX, and IT administrators managing supported SIP systems. Organizations needing technical support should consider the paid plans.

Siperb Mobile Softphone brings an existing SIP extension to iOS and Android. It is best suited to users and IT administrators who want mobile calling tied to a PBX they already operate. Its broad PBX compatibility and substantial call-handling toolkit make it a capable extension, though mobile registration is constrained to Siperb’s proxy mode.

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 while it is backgrounded, locked or restarted. That supports practical reachability without keeping the app open, but Proxy Registration Mode is the only mobile registration option and is required for push notifications.

Siperb also supports outbound registration, outbound trunk and inbound registration connections to PBXs or ITSPs. Web and desktop clients can use WebSocket Registration Mode to connect directly to a WebRTC-capable PBX without Siperb in the call path. That gives administrators a different connection choice for those clients, but 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 is more than a basic dialer: teams can handle transfers and conferences from the phone, while presence and call records help users keep track of activity. End-to-end encryption using TLS and DTLS-SRTP is specified for the mobile feature set, an important protection for organizations handling voice traffic.

The same Siperb account works across web, Windows, macOS, Linux, iOS and Android, with shared call history, contacts and settings. Users moving between devices keep a common account context rather than separate client identities. Browser calling and desktop apps broaden access beyond the mobile app; call recording and SIP support are also supported.

A documented REST API, with permanent tokens for external backend systems, gives developers a way to integrate Siperb with their own services. Separate developer embedding and reseller co-branding resources extend the product beyond end-user calling, although those are distinct from the core softphone proposition.

Pricing

Siperb has a free Personal plan and paid Business tiers. Personal costs nothing and has limited storage, seven days of SIP Trace Logs and Register Activity Log, community support, and no technical support. It is suitable for an individual or small-scale evaluation where short log retention and community help are acceptable; the lack of technical support is a meaningful drawback for business-critical deployments.

Business costs £2 a month, billed per month per domain user. It extends both log types to six months and includes technical support. This is the practical step up for teams that need a longer troubleshooting window and technical assistance. Business Pro costs £5 a month, also billed per month per domain user, and extends both logs to 12+ months while retaining technical support. It best fits organizations that need more historical records; the higher per-user cost buys longer retention rather than a stated expansion of calling features. Paid support covers technical issues with an approximately 24-hour response, compared with approximately 48 hours for free general-question support.

Platforms

Siperb supports Android, iOS, Linux, macOS, web and Windows. Mobile apps are available alongside desktop and browser calling, with shared account details across clients. The direct WebSocket option is specifically for web and desktop clients connecting to a WebRTC-capable PBX.

Who it's for

Siperb is a strong fit for organizations with an existing SIP PBX that want extensions to follow users onto phones, while keeping account details shared across desktop and browser clients. Its compatibility with several common PBX systems and broader SIP provisioning makes it relevant to IT administrators as well as end users. It is a weaker fit for teams that require mobile devices to register directly rather than through Siperb’s proxy, or for customers who need to install Siperb’s cloud-hosted components on their own servers; Siperb says those components cannot be self-hosted. Its open-source Browser Phone is the self-hosted alternative.

Pros and cons

• Pro: Broad SIP PBX compatibility, including Asterisk, FreePBX and FreeSWITCH, lets organizations use an existing extension setup.
• Pro: Push delivery and a full set of mobile call-handling tools support everyday office calling away from a desk.
• Pro: Shared contacts, settings and call history across six platform families make switching devices more coherent.
• Con: Proxy Registration Mode is mandatory on mobile, limiting organizations that require another registration approach.
• Con: Personal has limited storage, only seven days of logs and no technical support, which can be inadequate for operational troubleshooting.
• Con: Siperb’s cloud components cannot be installed on customer servers, ruling out a fully self-hosted Siperb deployment.

Alternatives

Choose Aria if a free softphone for personal, non-commercial use with unlimited calls and multi-account support is the priority. Blink offers free Linux, Mac and Windows downloads, but requires a SIP account for use. For a free app spanning mobile, desktop and web with unlimited users and installations on the App SipPulse plan, consider SipPulse Softphone.

Zoiper is another option: its free desktop edition is limited to non-commercial use, one account and two lines, while mobile team licensing is priced separately. AGEphone suits personal use at no cost, but business use requires AGEphone Cloud or AGEphone Business. Bria Solo is worth considering for readers seeking a paid cross-platform option with a free trial and a limited free personal tier.

Consider Linphone when open-source software or self-hosting is central; it is available across desktop, mobile and web, with proprietary licensing available for closed-source integration. PortSIP Softphone is a free alternative for users whose needs align with PortSIP PBX, including its free edition’s limit of two simultaneous calls and three extensions.

Browse more options in Softphone Software.

Verdict

Siperb Mobile Softphone is a good choice for teams that already run a compatible SIP PBX and want mobile extensions backed by push delivery, useful call controls and shared accounts across devices. The Business plans add longer log retention and technical support at clear per-domain-user monthly prices. Look elsewhere if mobile registration must bypass Siperb’s proxy or if self-hosting the cloud components is a requirement.