AgentPhone vs Zernio
Compare AgentPhone and Zernio side by side: iMessage features, channels, developer tools, pricing and compliance, checked on each provider's own site.
AgentPhone
Phone numbers with voice, SMS and iMessage for AI agents
- Starting price
- $3/month per number plus usage; iMessage from $150/month per line
- Free plan
- $5 starting credit, no card required
Zernio
One API for iMessage, SMS, WhatsApp, social DMs and calls
- Starting price
- $200/month per iMessage sender
- Free plan
- First 2 connected accounts free; free iMessage sandbox on a shared line
AgentPhone supports 44 of the 77 features compared here, and Zernio supports 57.
Where AgentPhone is ahead
Where Zernio is ahead
- Read receipts
- Edit and unsend
- Stickers
- Formatted text
- Rich link previews
- Voice messages
- Location sharing
- Shared numbers
and 9 more in the table below.
Feature comparison
| Feature | ||
|---|---|---|
| iMessage messaging | ||
| iMessage | ||
| Group chats | ||
| Group management | ||
| Group name and photo | ||
| Mentions | Not listed | Not listed |
| Tapbacks | ||
| Threaded replies | ||
| Typing indicators | ||
| Read receipts | Not listedThe pricing page mentions read receipts; no API or webhook for them is documented. | |
| Edit and unsend | Not listed | |
| Message effects | ||
| Animated text effects | Not listed | Not listed |
| Stickers | Not listed | |
| Formatted text | Not listed | |
| Attachments | ||
| Live Photos | Not listed | Not listed |
| Rich link previews | Not listed | |
| Voice messages | Not listed | |
| Contact cards | ||
| Polls | Not listed | Not listed |
| Chat backgrounds | Not listed | |
| Location sharing | Not listedThe API has location endpoints returning coordinates per number, but their use is not described. | |
| iMessage apps | Not listed | Not listed |
| Live app cards | Not listed | Not listed |
| Sender name and photo | ||
| FaceTime calls | Not listed | Not listedInbound FaceTime attempts show in the thread as call-typed messages. No calling documented. |
| Delivery status | ||
| iMessage availability check | Not listed | |
| Focus and Notify Anyway | Not listed | Not listed |
| Numbers and delivery | ||
| Managed lines | ||
| Dedicated numbers | ||
| Shared numbers | Not listed | |
| Bring your own number | Not listed | |
| Line pooling | Not listed | Not listedOne sender per profile; docs suggest spreading contacts across senders by hand. |
| SMS fallback | ||
| RCS fallback | ||
| Outbound-first messaging | ||
| Calls on the iMessage number | Not listed | |
| Other channels | ||
| SMS | ||
| RCS | ||
| Telegram | Not supportedNot offered | |
| Slack | Not supported | |
Not supported | Not supportedNot offered as a channel. iMessage senders can use an email handle. | |
| Phone calls | ||
| Apple Messages for Business | Not supportedNot offered | Not supportedNot offered |
| Unified channel API | ||
| Developer tools | ||
| REST API | ||
| TypeScript SDK | ||
| Python SDK | ||
| Other SDKs | Not listedDocs list only TypeScript and Python; an agentphone-go repo holds only a placeholder README. | |
| CLI | Not listedNo own CLI found; numbers can be provisioned through the Stripe Projects CLI. | |
| Webhooks | ||
| Signed webhooks | ||
| MCP server | ||
| Open source | ||
| Self-hosting | Not supportedHosted cloud service only | Not supportedHosted cloud service only |
| Local testing | Not listedThe free sandbox still needs your own phone or Apple ID. | |
| Custom channel providers | Not listed | Not listed |
| Event replay | ||
| OpenTelemetry | Not listed | Not listed |
| No-code integrations | ||
| CRM integrations | Not listed | |
| Built for AI agents | ||
| Agent framework | ||
| Agent framework integrations | ||
| Streaming replies | ||
| Agent group chats | Not listed | |
| Human handoff | ||
| Audit logs | Not listed | |
| Message history API | ||
| Plans and compliance | ||
| Free plan | ||
| Public pricing | ||
| No per-message fees | ||
| Uptime SLA | Not listedSite states 99.97% uptime; no contractual SLA found. | |
| Isolated infrastructure | Not listedSub-accounts isolate agents, numbers and data per client; no dedicated infrastructure offer found. | Not listed |
| SOC 2 Type II | ||
| GDPR |
Checked on each provider's own site and docs on 2026-10-25. “Not listed” means the provider does not mention it.
Pricing
AgentPhone
Pay as you go with $5 of starting credit: $3 per number a month, $0.13 to $0.22 a voice minute and $0.02 per SMS segment, with iMessage lines at $150 or $250 a month and no per-message charge.
Pricing model: usage-based, flat per line for iMessage
SourceZernio
An iMessage sender costs $200 a month plus Zernio's per-account fee, with a free sandbox; SMS, calls and outbound messages past 10,000 a month are metered.
Pricing model: flat per sender, plus per connected account and usage meters
SourceWhich should you choose?
Choose AgentPhone if you need chat backgrounds, iMessage availability check, local testing and agent group chats.
Choose Zernio if you need read receipts, edit and unsend, stickers and formatted text.
Frequently asked questions
AgentPhone supports 44 of the 77 features compared here, and Zernio supports 57. AgentPhone adds chat backgrounds, iMessage availability check, local testing and agent group chats. Zernio adds read receipts, edit and unsend, stickers, formatted text and rich link previews.
AgentPhone: Pay as you go with $5 of starting credit: $3 per number a month, $0.13 to $0.22 a voice minute and $0.02 per SMS segment, with iMessage lines at $150 or $250 a month and no per-message charge. Zernio: An iMessage sender costs $200 a month plus Zernio's per-account fee, with a free sandbox; SMS, calls and outbound messages past 10,000 a month are metered.
Zernio does not list chat backgrounds on its site or in its docs.
Zernio does not list iMessage availability check on its site or in its docs.
Zernio does not list local testing on its site or in its docs.