What is the difference between Inkbox and Miss Blue?

Inkbox supports 45 of the 77 features compared here, and Miss Blue supports 47. Inkbox adds message effects, contact cards, Slack, email and TypeScript SDK. Miss Blue adds group name and photo, edit and unsend, voice messages, location sharing and FaceTime calls.

How much do Inkbox and Miss Blue cost?

Inkbox: Free covers 3 identities with shared iMessage; Developer is $25 a month with a VoIP number; Startup is $167 a month with one dedicated iMessage number; Enterprise is custom. SMS/MMS and call minutes over allowance cost $0.03 each. Miss Blue: A free sandbox for testing, then $99 per dedicated number per month at the launch price (normally $198), with the usual $479 setup fee waived until October 31; FaceTime Audio ($250), phone calls ($75) or both ($300) are optional add-ons per line, and Enterprise is custom.

Does Miss Blue support message effects?

Miss Blue does not support message effects.

Does Miss Blue support contact cards?

Miss Blue does not list contact cards on its site or in its docs.

Does Miss Blue support Slack?

Miss Blue does not support Slack.

Inkbox vs Miss Blue

Compare Inkbox and Miss Blue side by side: iMessage features, channels, developer tools, pricing and compliance, checked on each provider's own site.

Inkbox

Email, phone, iMessage and A2A identity for AI agents

Starting price: $25/month (Developer); $167/month for a dedicated iMessage number (Startup)
Free plan: Free: 3 identities, shared iMessage up to 2,000 messages a month and 3 recipients at a time

Visit Inkbox Read more

Miss Blue

Dedicated iMessage line with API, team inbox and calling

Starting price: $99/month per number (launch price)
Free plan: Free sandbox; 30-minute live demo line

Visit Miss Blue Read more

Inkbox supports 45 of the 77 features compared here, and Miss Blue supports 47.

Where Inkbox is ahead

Where Miss Blue is ahead

and 2 more in the table below.

Feature comparison

Feature	Inkbox	Miss Blue
iMessage messaging
iMessage	SupportedShared router service on every plan, or a dedicated line from the Startup plan.	Supported
Group chats	SupportedDedicated lines only, 2 to 8 remote participants. Shared service is 1:1.	SupportedSend into an existing group by its chat_id and read group threads.
Group management	PartialCreate a group by sending to 2 to 8 numbers. No add or remove member API in V1.	SupportedCreate groups of 2 to 32 and add or remove members; leaving a group is not supported yet.
Group name and photo	Not listed	SupportedRename a group and set or remove its photo.
Mentions	Not listed	Not listed
Tapbacks	SupportedSend, replace and remove 7 tapbacks including eyes; inbound tapbacks arrive by webhook.	SupportedAdd or remove the six tapbacks; tapbacks from customers appear on the message.
Threaded replies	Supportedreply_to_message_id in 1:1 and group chats, with thread reads. Falls back to a plain reply.	SupportedQuoted replies with reply_to_message_id.
Typing indicators	PartialSend only, in 1:1 chats. Groups and inbound typing events are not supported.	SupportedSend typing, optional auto-typing on inbound iMessage, and contact typing via webhook.
Read receipts	PartialSend read receipts in 1:1 chats. No read status for your own sent messages is documented.	SupportedExplicit read receipts by API; outbound messages report read.
Edit and unsend	Not listed	PartialUnsend within Apple's 2-minute window. An edit endpoint is documented, but the FAQ says editing is not supported yet.
Message effects	Supported4 bubble and 9 full-screen send styles, in 1:1 and dedicated-line groups.	Not supportedThe errors page says effects are not a supported API operation yet.
Animated text effects	Not listed	Not supportedThe errors page says expressive text styles and effects are not supported yet.
Stickers	Not listed	Not listed
Formatted text	Not listed	Not listed
Attachments	SupportedOne media item per message, uploads up to 10 MiB. No media before the recipient's first reply.	SupportedImages, video, PDFs, Office files and more up to 100 MiB, one per send, or carousels of 2 to 20 images.
Live Photos	Not listed	Not listed
Rich link previews	Not listed	Not listed
Voice messages	Not listed	SupportedAudio-only sends use the native voice-note bubble by default.
Contact cards	PartialThe router sends the agent's contact card on connect. Sending other vCards is not documented.	Not listed
Polls	Not listed	Not listed
Chat backgrounds	Not listed	Not listed
Location sharing	Not listed	SupportedSend Find My requests, read the sharing state and watch live fixes over Server-Sent Events.
iMessage apps	Not listed	Not listed
Live app cards	Not listed	Not listed
Sender name and photo	SupportedDedicated lines share the identity's display name and avatar automatically.	SupportedSet and verify the number's Name and Photo Sharing profile by API.
FaceTime calls	Not listedCalls run over iMessage lines, but the docs do not say whether they are FaceTime.	PartialFaceTime Audio only, as a $250/month add-on per line.
Delivery status	Supportedimessage.sent, imessage.delivered and imessage.delivery_failed webhooks, per recipient in groups.	Supportedpending, sent, delivered, read and failed with a reason, by webhook or per-message callback.
iMessage availability check	SupportedReturns iMessage, SMS or RCS for any E.164 number.	SupportedLive iMessage and FaceTime registration lookup; a separate lookup reads your own past traffic.
Focus and Notify Anyway	Not listed	Not listed
Numbers and delivery
Managed lines	SupportedShared router lines and dedicated lines run by Inkbox. No Mac needed.	SupportedEach number runs on a Mac that Miss Blue operates; staff provision numbers within about 48 to 72 hours.
Dedicated numbers	SupportedStartup plan includes one dedicated iMessage number. VoIP numbers for calls and SMS from Developer.	Supported$99/month per number at the launch price (normally $198).
Shared numbers	SupportedFree and paid plans include shared iMessage. The human must text the router first.	SupportedShared-pool numbers are offered as a separate, labelled option.
Bring your own number	Not listed	SupportedTransfer an existing number in; staff complete it in about 1 to 2 weeks.
Line pooling	BetaOrganization-owned shared iMessage pools, beta and by request only.	SupportedAuto round robin spreads new contacts across a project's dedicated numbers, then keeps each on one.
SMS fallback	SupportedInkbox tries iMessage first and can fall back to SMS; was_downgraded marks it.	SupportedFalls back to RCS, or to SMS where RCS is unavailable, from the same number.
RCS fallback	PartialDocs describe SMS fallback, and the service field can report rcs. The transport cannot be chosen.	SupportedFalls back to RCS where the carrier and recipient support it.
Outbound-first messaging	PartialDedicated lines can start chats, up to 40 new recipients a day. Shared service needs the human to text first.	SupportedNew contacts are paced: 50 per number per day by default and 150 messages a day in total.
Calls on the iMessage number	SupportedAgents place and receive voice calls over shared and dedicated iMessage lines.	SupportedFaceTime Audio and phone calls from the number customers already message.
Other channels
SMS	SupportedSMS and MMS on dedicated VoIP numbers, US and Canada included. Group MMS is beta.	SupportedAs fallback from the iMessage number; the docs also describe Twilio SMS lines.
RCS	PartialOnly as a transport reported on iMessage lines; not a channel you can pick.	SupportedAs fallback when the carrier and recipient support it.
WhatsApp	Not supportedNot offered	Not supportedNot offered
Telegram	Not supported	Not supported
Slack	BetaSlack is in beta: read, reply, files and retained history search.	Not supportedNot offered as a channel; the Slack page is an integration guide.
Email	SupportedEach identity gets a mailbox, with custom domains and IMAP/SMTP access.	Not supportedNot offered as a channel; iMessage can be sent to Apple ID email addresses.
Phone calls	SupportedInbound and outbound calls with your own WebSocket agent or Inkbox Voice AI (beta).	PartialBrowser phone calls as a $75/month add-on; API keys cannot place regular phone calls.
Apple Messages for Business	Not supportedNot offered	Not supportedNot offered
Unified channel API	PartialOne identity and one webhook subscription across channels, but separate APIs per channel.	SupportediMessage with RCS and SMS fallback, groups and calls share one API and webhook stream.
Developer tools
REST API	Supported	Supported113 endpoints across 13 resources, with an OpenAPI file.
TypeScript SDK	Supported@inkbox/sdk	Not listedThe API is plain HTTP; no SDK package was found.
Python SDK	Supportedinkbox on PyPI	Not listed
Other SDKs	SupportedRust SDK (inkbox crate).	Not listed
CLI	Supported@inkbox/cli	Supportedmb, with installers for macOS, Linux and Windows.
Webhooks	Supported	Supported
Signed webhooks	SupportedHMAC-SHA256 with a per-identity signing key.	SupportedHex HMAC-SHA256 over timestamp and raw body; per-message callbacks are unsigned.
MCP server	SupportedRemote Streamable HTTP endpoint at inkbox.ai/mcp, with a separate ChatGPT endpoint.	Supportedmb mcp serves the CLI commands as MCP tools for Claude Code, Codex, Cursor and others.
Open source	PartialSDK, CLI, skills and examples are MIT on GitHub. The service is closed.	Not supportedThe CLI repo holds builds and installers without a license; the service is closed.
Self-hosting	Not listed	Not listed
Local testing	Not listed	Supportedmb_sandbox_ keys simulate outcomes and signed webhooks on a virtual number, with no phone.
Custom channel providers	Not listed	Not listed
Event replay	SupportedDelivery log with replay. Incoming-call and Slack deliveries cannot be replayed.	PartialPer-endpoint delivery log and history sync; docs say to poll GET /v1/messages to repair missed events.
OpenTelemetry	Not listed	Not listed
No-code integrations	Not listed	BetaGoHighLevel connector is in beta; the Zapier, Make and n8n pages are setup guides.
CRM integrations	Not listed	BetaGoHighLevel connector in beta; HubSpot and Salesforce pages describe API builds set up in onboarding.
Built for AI agents
Agent framework	PartialIdentity layer with contact memories across email, texts and calls. No conversation framework.	PartialNo agent SDK; offers a managed conversational AI add-on and multi-step automations.
Agent framework integrations	SupportedPlugins for Hermes Agent, OpenClaw, OpenCode, Codex, Claude Code and DeepSeek Harness.	PartialGuide pages for Vercel AI SDK, Chat SDK, LangChain and Claude Agent SDK; no adapter package found.
Streaming replies	Not listed	Not listed
Agent group chats	Not listedAgents can reach each other over A2A tasks, but not in group chats.	Not listed
Human handoff	PartialPeople can reply from the Console, and Voice AI can transfer a call. No handoff controls for agents.	SupportedShared Message Center for human takeover, with internal notes and resolving.
Audit logs	Not listed	Not listed
Message history API	SupportedList and read conversations and threads, with search on texts and email.	SupportedThread history by API and a conversation sync from the line's Mac.
Plans and compliance
Free plan	SupportedFree: 3 identities, shared iMessage up to 2,000 messages a month and 3 recipients at a time.	SupportedFree sandbox with simulated sends, plus a 30-minute live demo line by texting DEMO.
Public pricing	Supported	Supported
No per-message fees	PartialiMessage is capped per plan with no per-message fee. Extra SMS/MMS and call minutes cost $0.03 each.	Supported
Uptime SLA	Not listed	PartialEnterprise only: contracted service terms; no uptime figure published.
Isolated infrastructure	PartialDedicated iMessage infrastructure is listed for Enterprise only.	SupportedDedicated numbers run on hardware assigned to you; Enterprise adds dedicated equipment.
SOC 2 Type II	Not listed	Not listed
GDPR	Not listedThe DPA names the CCPA only; GDPR is not mentioned.	Not listed

Feature

Inkbox

Miss Blue

iMessage messaging

iMessage

Shared router service on every plan, or a dedicated line from the Startup plan.

Group chats

Dedicated lines only, 2 to 8 remote participants. Shared service is 1:1.

Send into an existing group by its chat_id and read group threads.

Group management

PartialCreate a group by sending to 2 to 8 numbers. No add or remove member API in V1.

Create groups of 2 to 32 and add or remove members; leaving a group is not supported yet.

Group name and photo

Not listed

Rename a group and set or remove its photo.

Mentions

Not listed

Tapbacks

Send, replace and remove 7 tapbacks including eyes; inbound tapbacks arrive by webhook.

Add or remove the six tapbacks; tapbacks from customers appear on the message.

Threaded replies

reply_to_message_id in 1:1 and group chats, with thread reads. Falls back to a plain reply.

Quoted replies with reply_to_message_id.

Typing indicators

PartialSend only, in 1:1 chats. Groups and inbound typing events are not supported.

Send typing, optional auto-typing on inbound iMessage, and contact typing via webhook.

Read receipts

PartialSend read receipts in 1:1 chats. No read status for your own sent messages is documented.

Explicit read receipts by API; outbound messages report read.

Edit and unsend

Not listed

PartialUnsend within Apple's 2-minute window. An edit endpoint is documented, but the FAQ says editing is not supported yet.

Message effects

4 bubble and 9 full-screen send styles, in 1:1 and dedicated-line groups.

Not supportedThe errors page says effects are not a supported API operation yet.

Animated text effects

Not listed

Not supportedThe errors page says expressive text styles and effects are not supported yet.

Stickers

Not listed

Formatted text

Not listed

Attachments

One media item per message, uploads up to 10 MiB. No media before the recipient's first reply.

Images, video, PDFs, Office files and more up to 100 MiB, one per send, or carousels of 2 to 20 images.

Live Photos

Not listed

Rich link previews

Not listed

Voice messages

Not listed

Audio-only sends use the native voice-note bubble by default.

Contact cards

PartialThe router sends the agent's contact card on connect. Sending other vCards is not documented.

Not listed

Polls

Not listed

Chat backgrounds

Not listed

Location sharing

Not listed

Send Find My requests, read the sharing state and watch live fixes over Server-Sent Events.

iMessage apps

Not listed

Live app cards

Not listed

Sender name and photo

Dedicated lines share the identity's display name and avatar automatically.

Set and verify the number's Name and Photo Sharing profile by API.

FaceTime calls

Not listedCalls run over iMessage lines, but the docs do not say whether they are FaceTime.

PartialFaceTime Audio only, as a $250/month add-on per line.

Delivery status

imessage.sent, imessage.delivered and imessage.delivery_failed webhooks, per recipient in groups.

pending, sent, delivered, read and failed with a reason, by webhook or per-message callback.

iMessage availability check

Returns iMessage, SMS or RCS for any E.164 number.

Live iMessage and FaceTime registration lookup; a separate lookup reads your own past traffic.

Focus and Notify Anyway

Not listed

Numbers and delivery

Managed lines

Shared router lines and dedicated lines run by Inkbox. No Mac needed.

Each number runs on a Mac that Miss Blue operates; staff provision numbers within about 48 to 72 hours.

Dedicated numbers

Startup plan includes one dedicated iMessage number. VoIP numbers for calls and SMS from Developer.

$99/month per number at the launch price (normally $198).

Shared numbers

Free and paid plans include shared iMessage. The human must text the router first.

Shared-pool numbers are offered as a separate, labelled option.

Bring your own number

Not listed

Transfer an existing number in; staff complete it in about 1 to 2 weeks.

Line pooling

BetaOrganization-owned shared iMessage pools, beta and by request only.

Auto round robin spreads new contacts across a project's dedicated numbers, then keeps each on one.

SMS fallback

Inkbox tries iMessage first and can fall back to SMS; was_downgraded marks it.

Falls back to RCS, or to SMS where RCS is unavailable, from the same number.

RCS fallback

PartialDocs describe SMS fallback, and the service field can report rcs. The transport cannot be chosen.

Falls back to RCS where the carrier and recipient support it.

Outbound-first messaging

PartialDedicated lines can start chats, up to 40 new recipients a day. Shared service needs the human to text first.

New contacts are paced: 50 per number per day by default and 150 messages a day in total.

Calls on the iMessage number

Agents place and receive voice calls over shared and dedicated iMessage lines.

FaceTime Audio and phone calls from the number customers already message.

Other channels

SMS

SMS and MMS on dedicated VoIP numbers, US and Canada included. Group MMS is beta.

As fallback from the iMessage number; the docs also describe Twilio SMS lines.

RCS

PartialOnly as a transport reported on iMessage lines; not a channel you can pick.

As fallback when the carrier and recipient support it.

Not supportedNot offered

Not supported

Slack

BetaSlack is in beta: read, reply, files and retained history search.

Not supportedNot offered as a channel; the Slack page is an integration guide.

Each identity gets a mailbox, with custom domains and IMAP/SMTP access.

Not supportedNot offered as a channel; iMessage can be sent to Apple ID email addresses.

Phone calls

Inbound and outbound calls with your own WebSocket agent or Inkbox Voice AI (beta).

PartialBrowser phone calls as a $75/month add-on; API keys cannot place regular phone calls.

Apple Messages for Business

Not supportedNot offered

Unified channel API

PartialOne identity and one webhook subscription across channels, but separate APIs per channel.

iMessage with RCS and SMS fallback, groups and calls share one API and webhook stream.

Developer tools

REST API

113 endpoints across 13 resources, with an OpenAPI file.

TypeScript SDK

@inkbox/sdk

Not listedThe API is plain HTTP; no SDK package was found.

Python SDK

inkbox on PyPI

Not listed

Other SDKs

Rust SDK (inkbox crate).

Not listed

CLI

@inkbox/cli

mb, with installers for macOS, Linux and Windows.

Webhooks

Signed webhooks

HMAC-SHA256 with a per-identity signing key.

Hex HMAC-SHA256 over timestamp and raw body; per-message callbacks are unsigned.

MCP server

Remote Streamable HTTP endpoint at inkbox.ai/mcp, with a separate ChatGPT endpoint.

mb mcp serves the CLI commands as MCP tools for Claude Code, Codex, Cursor and others.

Open source

PartialSDK, CLI, skills and examples are MIT on GitHub. The service is closed.

Not supportedThe CLI repo holds builds and installers without a license; the service is closed.

Self-hosting

Not listed

Local testing

Not listed

mb_sandbox_ keys simulate outcomes and signed webhooks on a virtual number, with no phone.

Custom channel providers

Not listed

Event replay

Delivery log with replay. Incoming-call and Slack deliveries cannot be replayed.

PartialPer-endpoint delivery log and history sync; docs say to poll GET /v1/messages to repair missed events.

OpenTelemetry

Not listed

No-code integrations

Not listed

BetaGoHighLevel connector is in beta; the Zapier, Make and n8n pages are setup guides.

CRM integrations

Not listed

BetaGoHighLevel connector in beta; HubSpot and Salesforce pages describe API builds set up in onboarding.

Built for AI agents

Agent framework

PartialIdentity layer with contact memories across email, texts and calls. No conversation framework.

PartialNo agent SDK; offers a managed conversational AI add-on and multi-step automations.

Agent framework integrations

Plugins for Hermes Agent, OpenClaw, OpenCode, Codex, Claude Code and DeepSeek Harness.

PartialGuide pages for Vercel AI SDK, Chat SDK, LangChain and Claude Agent SDK; no adapter package found.

Streaming replies

Not listed

Agent group chats

Not listedAgents can reach each other over A2A tasks, but not in group chats.

Not listed

Human handoff

PartialPeople can reply from the Console, and Voice AI can transfer a call. No handoff controls for agents.

Shared Message Center for human takeover, with internal notes and resolving.

Audit logs

Not listed

Message history API

List and read conversations and threads, with search on texts and email.

Thread history by API and a conversation sync from the line's Mac.

Plans and compliance

Free plan

Free: 3 identities, shared iMessage up to 2,000 messages a month and 3 recipients at a time.

Free sandbox with simulated sends, plus a 30-minute live demo line by texting DEMO.

Public pricing

No per-message fees

PartialiMessage is capped per plan with no per-message fee. Extra SMS/MMS and call minutes cost $0.03 each.

Uptime SLA

Not listed

PartialEnterprise only: contracted service terms; no uptime figure published.

Isolated infrastructure

PartialDedicated iMessage infrastructure is listed for Enterprise only.

Dedicated numbers run on hardware assigned to you; Enterprise adds dedicated equipment.

SOC 2 Type II

Not listed

GDPR

Not listedThe DPA names the CCPA only; GDPR is not mentioned.

Not listed

Checked on each provider's own site and docs on 2026-10-25. “Not listed” means the provider does not mention it.

Pricing

Inkbox

Free covers 3 identities with shared iMessage; Developer is $25 a month with a VoIP number; Startup is $167 a month with one dedicated iMessage number; Enterprise is custom. SMS/MMS and call minutes over allowance cost $0.03 each.

Pricing model: monthly plans with allowances, plus per-unit SMS/MMS and call-minute overage

Source

Miss Blue

A free sandbox for testing, then $99 per dedicated number per month at the launch price (normally $198), with the usual $479 setup fee waived until October 31; FaceTime Audio ($250), phone calls ($75) or both ($300) are optional add-ons per line, and Enterprise is custom.

Pricing model: flat per line

Source