250,000 Clinicians on One Push Stack
Hospital voice was wired into desks, nurse stations, and overhead pages, while the clinicians who depend on it move across floors every shift.
250,000+ monthly active clinicians on embedded voice that moves with them, inside the Mobile Heartbeat platform.
Hospital communications were stuck in a stationary model long after the work that depends on them stopped being stationary.
Nurses, physicians, and clinical staff move across floors, units, and buildings every shift. But the voice infrastructure they were given to coordinate on was wired into desks, nurse stations, and overhead pages. The result was a steady gap between where clinical decisions actually happen and where the tools to coordinate them lived.
Mobile Heartbeat had built a platform to close that gap. Clinical messaging, secure team coordination, broadcast alerts, all designed for clinicians on the move. The missing layer was voice that worked on the same model. Not a softphone bolted on top, not a separate dialer clinicians had to switch into. Voice that was a peer to the rest of the platform, embedded in the same workflow, on the same devices clinicians were already carrying.
The reliability bar was non-negotiable. In a clinical setting, a missed call is not a customer-experience issue. It is a patient safety event.
Mobile Heartbeat
clinical communications platform serving hospital systems across the United States
250,000+ monthly active clinical users
on Cloud Softphone, embedded inside the Mobile Heartbeat platform
Walk-and-talk clinical workflows
voice and messaging on mobile devices that move with clinicians across hospital floors
Acrobits is invisible
to end users and to hospital IT teams; Mobile Heartbeat owns the experience end-to-end
Mobile Heartbeat partnered with Acrobits to bring Cloud Softphone into its platform as the voice layer.
The result: 250,000+ monthly active clinical users running on an embedded, white-labeled softphone that operates inside the Mobile Heartbeat experience. Clinicians do not download a separate dialer. They do not switch apps to take a call. The voice product behaves like part of the platform, because it is.
Push reliability held at scale across iOS and Android, including the backgrounded and battery-optimized states where consumer-grade softphones tend to silently miss calls. Calls ring. Messages deliver. Clinical workflows that depend on real-time coordination keep working.
How they used Acrobits
White-labeled Cloud Softphone, embedded in the platform. Clinicians see Mobile Heartbeat's brand, UI, and workflow. Hospital IT teams contract with Mobile Heartbeat. Acrobits sits underneath, where the clinical user never has to think about it.
A technical foundation built for the use case. SIPIS local push delivers calls reliably to backgrounded and battery-optimized devices. CallKit on iOS and native Android telephony integration keep the call presentation native to the device.
An encryption stack hospital IT can audit. TLS for signaling, SRTP for media, ZRTP available end-to-end, aligning with the security posture hospital IT teams require. Acrobits supports Mobile Heartbeat; Mobile Heartbeat supports the hospital systems on its platform.
What they needed
- Voice that survived locked screens, backgrounded apps, and battery-aggressive Androids at clinical-grade reliability: every call, every shift, every device
- A voice layer that behaved like a peer to messaging and team coordination, not a separate dialer clinicians had to switch into
- An embedded SDK they could compose into their own platform, not a stand-alone app they had to convince hospitals to deploy alongside theirs
- The Mobile Heartbeat brand and workflow on every clinical screen, with Acrobits invisible to clinicians and to hospital IT
- An encryption stack hospital security teams could audit on its own terms: TLS, SRTP, ZRTP
Technical detail
Features that did the work
SIPIS local push
sub-half-second call delivery on backgrounded and battery-optimized devices.
CallKit (iOS) + native Android telephony
calls land on the device's own call screen.
Encryption stack (TLS / SRTP / ZRTP)
auditable for hospital security teams.
Fully embedded SDK integration
the calling layer runs inside Mobile Heartbeat's platform; Acrobits is invisible to clinicians, to hospital IT, and to the hospital's security auditors.
Class 5 softswitch compatibility
works with hospital telephony infrastructure.
Active-user billing
scales with usage, not provisioned headcount.
In clinical settings, the softphone layer has to be invisible and bulletproof.
Both at once.