Top 5 Business VoIP Softphones | Comparison Guide
A practical comparison of the top five VoIP softphone apps for UK business users: Microsoft Teams (Teams Phone), 3CX, Zoiper, RingCentral, and Acrobits Groundwire. Features, cross-platform support, and monthly costs compared — from free to £25 per user per month.
Ollie Hill-Haimes
Sales Director
Softphone Comparison: Choosing the Right App for Your Team
With most major VoIP platforms including native softphone apps, the choice of softphone is often determined by the VoIP platform you choose. However, there are scenarios where a third-party or platform-agnostic softphone adds value — particularly for mobile users, businesses running multiple VoIP platforms, or those whose provider's native app has reliability gaps. This comparison covers the top five options.
Microsoft Teams — Best for M365-Integrated Calling
Platform: Windows, Mac, iOS, Android, Linux (limited)
Cost: Included with Teams Phone licence (£6–£12/user/month)
With a Teams Phone licence and calling plan, the Teams application handles all business calling — internal and external. The interface integrates calls with chat, meetings, files, and calendars. For businesses already using Teams for collaboration, adding calling capability in the same interface eliminates context switching.
Key strengths: No additional app, native M365 integration, presence and call status visible to colleagues, strong enterprise security.
Limitations: Less flexible than standalone SIP softphones for multi-platform environments; call recording requires Teams Premium or compliance recording partner.
3CX Web Client / Mobile App — Best for 3CX Platforms
Platform: Browser (all OS), iOS, Android
Cost: Included with 3CX licence
3CX's softphone ecosystem is well-developed. The web client requires no installation — it runs in any modern browser. Features include HD calls, video meetings, chat, presence, and CRM screen-popping. The mobile app supports background calling and push notifications on iOS and Android.
Key strengths: Browser-based (no installation), video conferencing included, cross-platform, no additional cost, strong feature set.
Limitations: Requires 3CX platform; mobile background calling occasionally needs reconfiguration.
Zoiper — Best Platform-Agnostic Option
Platform: Windows, Mac, Linux, iOS, Android
Cost: Free (Lite) or approximately £3–£5 one-off (Pro)
Zoiper is a standalone SIP softphone compatible with any SIP VoIP platform. It is the go-to choice when the native softphone is inadequate or when staff use multiple VoIP systems. The Pro version adds HD video, encryption, and advanced codec support.
Key strengths: Works with any SIP system, very low cost, broad platform support, reliable.
Limitations: Does not integrate with the management features of specific platforms (analytics, recording management) as deeply as native apps.
RingCentral App — Best for RingCentral Deployments
Platform: Windows, Mac, iOS, Android
Cost: Included with RingCentral plan (£15–£25/user/month)
RingCentral's unified app combines calling, messaging, and video in one polished interface. It integrates natively with RingCentral's analytics, call recording management, and 250+ CRM and business app integrations. The mobile app is well-regarded for background calling reliability.
Key strengths: Full platform integration, polished UI, strong integrations, reliable mobile background calling.
Limitations: Locked to the RingCentral platform; higher underlying platform cost.
Acrobits Groundwire — Best Mobile-First Softphone
Platform: iOS, Android
Cost: Approximately £7–£10 one-off purchase
Groundwire is consistently rated as the most reliable mobile SIP softphone for background calling. For field-based staff, sales teams, or anyone who must reliably receive business calls on a smartphone, Groundwire's push notification and call handling reliability outperforms many native platform apps. Works with any SIP VoIP platform.
Key strengths: Best mobile background calling reliability, platform-agnostic, low one-off cost.
Limitations: Mobile only; no desktop version.
Summary
- Microsoft 365 users: Teams (Teams Phone)
- 3CX deployments: 3CX Web Client / Mobile
- RingCentral deployments: RingCentral App
- Platform-agnostic need: Zoiper
- Best mobile reliability: Groundwire
Looking for the Right VoIP Softphone?
AMVIA helps businesses select and deploy the right softphone for their VoIP platform — with configuration and training included.
Frequently Asked Questions
Yes, as long as the softphone supports SIP and you have access to your SIP account credentials. Most third-party softphones (Zoiper, Groundwire) work with any SIP-compatible VoIP platform. The trade-off is that deep platform integrations (analytics, recording management) may not be available through a third-party client.
Teams is the best choice for businesses already using Microsoft 365 and Teams Phone. Its tight M365 integration and single-interface approach are genuine advantages. For businesses on non-Microsoft VoIP platforms, Teams is not applicable as a general-purpose SIP softphone — it requires the Teams Phone infrastructure. <strong>Microsoft Teams Phone has surpassed 26 million PSTN users worldwide</strong> as of December 2025 — up from 20 million in April 2024, representing 30% growth in 20 months. <em>(UC Today)</em>
Zoiper Lite is a well-regarded free SIP softphone available for Windows, Mac, Linux, iOS, and Android. It supports standard VoIP calls on any SIP platform without charge. For businesses needing video or encrypted calls, the Pro upgrade is worth the low one-off cost.
Zoiper offers a Chrome extension and web version that works on Chromebooks. 3CX's web client runs in any browser including Chrome on Chromebook. Microsoft Teams has a web version for Chromebook. Platform availability varies — confirm browser-based access is available for your chosen platform before deploying on Chromebooks.
Missed calls on mobile softphones are usually caused by push notification failures or background app restrictions. To improve reliability: ensure the app has unrestricted background access in device settings, use a platform with strong push notification implementation (Groundwire, 3CX, RingCentral), and keep the device connected to Wi-Fi or a reliable 4G network. Groundwire is specifically recommended for the best mobile background calling reliability.
A VoIP call uses approximately 100 kbps, which equates to roughly 7 MB per minute of call time. A 30-minute call uses approximately 200 MB of data. For moderate call volumes, this is manageable on a standard business mobile data plan. Businesses with staff making many long calls on mobile data should ensure adequate data allowances are included in their mobile contracts.
Related Reading
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