Should you build or buy Push-to-Talk over Cellular (PoC)?
Push-to-talk over cellular software turns a smartphone or rugged handset into a radio-style group communication device over a cellular or Wi-Fi network instead of a licensed radio frequency. Buyers are field workforces, dispatchers, and frontline teams who need instant group voice without carrying separate two-way radios.
Buy a managed PoC subscription and integrate it through the vendor's API or SDK where your dispatch workflow needs it. Match the tier to the risk: ordinary field crews need reliable group PTT and admin; life-safety operations need a service and carrier configuration documented for MCPTT and QoS.
Build it, buy it, or bridge?
When building makes sense
There is essentially no build case for push-to-talk over cellular. This is commodity workforce communication, and open-source components exist, tools like Mumble and Janus, and research-grade MCPTT stacks, but none of them are shown running as a production replacement for an enterprise's frontline radio system. Fraunhofer built an open-source MCPTT proof of concept on a private 5G network specifically to test the idea, and it did not fully meet the performance limits the standard requires, a telling result from a team trying to prove the concept could work. Carrier priority and quality of service depend on entitlements the carrier grants, not on anything an app can add through software alone, so a self-built client still needs a carrier relationship it cannot build itself. The honest comparison is against a subscription running $6.80 to $15 per user a month that already works.
When buying makes sense
Buying is the only real path here, and the decision is which tier matches your risk. Zello Work prices around $6.80 to $12.75 per user per month on an annual plan and is used by companies like LafargeHolcim across roughly 200 trucks. ESChat runs $5.99 per user per month for its commercial cloud service and offers a government and FedRAMP-certified tier for public safety use, with LA-RICS running a P25-integrated MCPTT launch on it in 2026. Motorola's WAVE PTX prices around $8 per user for the app and is used by organizations like Amey on Transport Scotland contracts, plus smaller businesses; one customer, a canoe and campground rental operator, reports the app removing wait time between staff coordinating on jobs. Match the tier to the risk: ordinary field crews need reliable group audio and basic admin tools, while life-safety operations need a service documented for the compliance and priority standards they answer to.
The desk read
Build-versus-buy analysis for Push-to-Talk over Cellular (PoC) is being written. In the meantime, the framework that drives every B4 call is on the B4 Index page.
Frequently asked
Is there a real open-source alternative to commercial push-to-talk services?
Not in production for enterprise use. Open-source pieces like Mumble and Janus exist, and researchers at Fraunhofer built an MCPTT proof of concept on private 5G, but it did not fully meet the standard's performance requirements. No enterprise in available research runs an open-source stack as its actual frontline communication system.
What's the difference between a basic plan and a public-safety tier?
A basic commercial plan gives reliable group voice, messaging, and location tracking for field crews. A public-safety or FedRAMP tier, like ESChat's government cloud option, adds compliance certification, radio bridging, and carrier priority arrangements that life-safety operations need and ordinary businesses generally don't.
Do these apps replace two-way radios entirely?
Often not fully. Several vendors, including ESChat and Motorola, sell gateway hardware specifically to bridge the cellular app with existing land mobile radio systems, since many organizations run both during a transition or keep radios as a backup where cellular coverage is unreliable.
How much does push-to-talk over cellular cost per user?
Roughly $6 to $15 per user per month, depending on tier and vendor. Entry plans from Zello and ESChat sit at $6 to $8 (ESChat's base commercial tier is $5.99); Zello's higher Plus tier, with location tracking and API access, runs $12.75 to $15 per user per month. Government, FedRAMP, and radio-gateway add-ons cost more and are usually priced separately from the base subscription.