SendiMessage vs Linq

SendiMessage supports 27 of the 77 features compared here, and Linq supports 63.

Feature comparison

Feature	SendiMessage	Linq
iMessage messaging
iMessage	SupportedWhere the line type and recipient support it; iMessage-capable lines are confirmed during onboarding.	Supported
Group chats	Not listed	SupportedPro plan. Up to 31 recipients. No read or delivery receipts in groups.
Group management	Not listed	SupportedAdd and remove participants and leave a group, iMessage groups only, 3-member minimum.
Group name and photo	Not listed	SupportedSet display_name and group_chat_icon on group chats.
Mentions	Not listed	SupportedGroup chats only. Notifies iMessage recipients even in a muted chat.
Tapbacks	Not listed	SupportedSix classic tapbacks or any emoji, send and receive via reaction webhooks.
Threaded replies	Not listed	Supportedreply_to with optional part_index. iMessage only.
Typing indicators	Not listed	SupportedSend and receive, in direct and group chats. iMessage only.
Read receipts	Not listed	SupportedMark chats read and receive message.read. One-to-one chats only.
Edit and unsend	Not listed	PartialEdit text up to 5 times within 15 minutes. Delete does not unsend from the recipient's device.
Message effects	Not listed	Supported11 screen and 4 bubble effects.
Animated text effects	Not listed	Supportedtext_decorations animations: big, small, shake, nod, explode, ripple, bloom, jitter.
Stickers	Not listed	SupportedPeel emoji or images onto messages, send stickers, or place them inline in text.
Formatted text	Not listed	SupportedBold, italic, underline and strikethrough ranges, plus animated text. iMessage only.
Attachments	SupportedOne photo, video, audio file or PDF up to 50 MiB per message, via media_url.	SupportedUp to 10MB by URL, 100MB with pre-upload.
Live Photos	Not listed	Not listed
Rich link previews	Not listed	Supportedlink parts render as rich previews on iMessage and RCS.
Voice messages	PartialAudio files send as media, with webm and ogg converted to m4a; a native voice-note bubble is not stated.	SupportedDedicated voice memo endpoint renders the native iMessage voice bubble.
Contact cards	Not listed	SupportedSend .vcf files as media parts.
Polls	Not listed	SupportedCreate, add options, vote and read tallies, with poll webhooks. Not as a chat's first message.
Chat backgrounds	Not listed	SupportedColor, animated or photo backgrounds, in direct and group chats.
Location sharing	Not listed	SupportedRequest, read and stop Find My shares. Live location is a $79/mo add-on on Pro.
iMessage apps	Not listed	SupportedPro plan. Cards from your own Messages extension, or Linq-hosted cards (Experiences).
Live app cards	Not listed	SupportedUpdate App Card replaces a delivered iMessage app or Experience card in place.
Sender name and photo	Not listed	SupportedContact card API sets name and photo, shared per chat via Name and Photo Sharing.
FaceTime calls	Not listed	Not supportedDocs say the API does not place or answer calls.
Delivery status	SupportedQUEUED, SENT and ERROR on /status, DELIVERED on history rows, and an outbound webhook.	Supportedsent, delivered, read and failed webhooks. Groups report sent only.
iMessage availability check	SupportedGET /lookup says iMessage or SMS for a number, cached for 7 days.	Supportedcheck_imessage and check_rcs endpoints.
Focus and Notify Anyway	Not listed	Not listed
Numbers and delivery
Managed lines	SupportedLines are provisioned, operated and monitored by SendiMessage after a use-case review.	Supported
Dedicated numbers	Supported$129 per line per month.	SupportedPaid lines are dedicated. Provisioned by Linq, no self-serve number API.
Shared numbers	Not supportedSendiMessage says it offers no shared numbers or pools.	SupportedFree Hobby tier uses a Shared Line, inbound-first, 20 contacts.
Bring your own number	Not listed	Not listed
Line pooling	Not listedOmitting line_handle lets any active line send; load balancing is not described.	SupportedManaged load balancing (Pro): send without from and Linq picks and fails over lines.
SMS fallback	SupportedOnly where configured on the line; one-way and not selectable per request.	Supported
RCS fallback	Not listedHistory rows can carry RCS, but routing is described as iMessage, then SMS.	SupportedOrder is iMessage, then RCS, then SMS.
Outbound-first messaging	SupportedLines carry hourly and daily new-conversation limits; replies in existing threads are not limited.	SupportedFree Hobby tier is inbound-first. Docs recommend inbound-first flows to avoid flagging.
Calls on the iMessage number	PartialInbound call forwarding per line; no calling API.	PartialAPI forwards inbound calls on the line; outbound needs caller-ID masking via another provider.
Other channels
SMS	SupportedSMS lines, or SMS fallback on hybrid lines.	Supported
RCS	Not listedHistory rows can carry RCS; sending over RCS is not documented.	Supported
WhatsApp	Not supportedNot offered	BetaSeparate WhatsApp API in beta. Access by request, no SLA.
Telegram	Not supported	Not supportedNot offered
Slack	Not supportedNot offered as a channel; Slack appears as an integration guide.	Not supported
Email	Not supportedNot offered	Not supportedNot offered. iMessage can be sent to Apple ID email handles.
Phone calls	PartialInbound call forwarding only; the voice AI pages cover texting after calls run elsewhere.	PartialAPI does not place or answer calls; it forwards inbound calls. Calling lives in the Linq Blue app.
Apple Messages for Business	Not supportedNot offered	Not listedAI context page mentions it, but no product page or docs were found.
Unified channel API	SupportedOne send endpoint and message history across SMS, iMessage-capable and hybrid lines.	PartialiMessage, RCS and SMS share one API. WhatsApp is a separate API with its own keys and SDKs.
Developer tools
REST API	Supported	Supported
TypeScript SDK	Supportedsendimessage on npm with TypeScript definitions, MIT.	Supported@linqapp/sdk
Python SDK	Supportedsendimessage on PyPI, standard library only, MIT.	Supportedlinq-python
Other SDKs	SupportedOfficial PHP and Go SDKs, MIT.	SupportedOfficial Go SDK.
CLI	Not listed	Supported@linqapp/cli: signup, sending, and a local webhook listener.
Webhooks	Supportedreceive, outbound, line_blocked and line_unblocked events.	Supported
Signed webhooks	SupportedHMAC-SHA256 SendiMessage-Signature with a timestamp for replay protection.	SupportedHMAC-SHA256, Standard Webhooks format, with replay protection.
MCP server	Not listed	Supported@linqapp/sdk-mcp with docs search and code execution tools.
Open source	PartialSDKs are MIT on GitHub; the platform is closed.	PartialSDKs, CLI and adapters are Apache-2.0 or MIT on GitHub. The messaging platform is closed.
Self-hosting	Not listed	Not supportedLinq describes itself as fully managed, in contrast to self-hosted options.
Local testing	Not supportedSendiMessage says there is no sandbox; the site playground only simulates with example data.	Not listedThe CLI streams webhooks locally, but tests still use a real phone.
Custom channel providers	Not listed	Not listed
Event replay	PartialFailed deliveries retry with backoff; reconcile missed events from GET /v2/messages.	PartialRetries for 30 minutes; after that, re-fetch chats or ask Linq for a manual replay.
OpenTelemetry	Not listed	PartialW3C trace IDs on every response and webhook for OTel backends. No export of Linq spans by default.
No-code integrations	PartialGuides only: Zapier through Webhooks by Zapier, GoHighLevel through workflow webhook actions.	SupportedLinq Blue works as a GoHighLevel messaging provider. No n8n, Make or Zapier found for the API.
CRM integrations	PartialAPI integration guides for Salesforce, HubSpot and others; no native connectors.	SupportedVia Linq Blue: GoHighLevel, HubSpot and Salesforce.
Built for AI agents
Agent framework	Not supportedSendiMessage says it is the transport, not the brain, and does not run your model.	PartialNo own framework. Maintains a Vercel Chat SDK adapter and OpenClaw and Hermes plugins.
Agent framework integrations	Not listed	SupportedLinq-maintained Vercel Chat SDK adapter, plus OpenClaw and Hermes Agent plugins.
Streaming replies	Not listed	Not supportedDocs say the Chat SDK adapter buffers streams into one final message.
Agent group chats	Not listed	Not listed
Human handoff	Not listedA dashboard team inbox shows replies; takeover of agent conversations is not described.	Not listed
Audit logs	Not listed	SupportedDashboard Activity page plus account-change webhooks with actor and origin.
Message history API	SupportedFilterable history with cursor pagination and per-conversation threads.	Supported
Plans and compliance
Free plan	Not supportedNo free plan or sandbox; the Developer Pilot costs $129 for the first month.	SupportedHobby: $0, up to 20 contacts, through the CLI.
Public pricing	Supported	SupportedPro from $260/mo. Enterprise is custom.
No per-message fees	PartialFlat $129 per line, but SMS, carrier or provider usage may be billed separately.	Supported
Uptime SLA	Not supportedThe security page says SendiMessage does not advertise guaranteed uptime.	SupportedContractual SLAs on the Enterprise plan; marketing cites 99.95%
Isolated infrastructure	SupportedEach line is provisioned to one organization and never shared across customers.	SupportedDedicated lines across 4 data centers on paid plans; Hobby uses a shared line
SOC 2 Type II	Not supportedSendiMessage says it does not hold SOC 2 certification.	SupportedType I and Type II, reports for 2022, 2024, 2025 and 2026.
GDPR	Not listed	SupportedDPA covers GDPR and UK GDPR, with Standard Contractual Clauses.

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

Pricing

Which should you choose?

Choose SendiMessage if its pricing fits better: it does not support anything here that Linq lacks.

Choose Linq if you need group chats, group management, group name and photo and mentions.

Frequently asked questions

• Photon vs SendiMessage

• Photon vs Linq
• Blooio vs Linq
• Sendblue vs Linq
• Zernio vs Linq
• LoopMessage vs Linq
• Blue Reacher vs Linq
• Chert vs Linq
• Miss Blue vs Linq
• Bland vs Linq
• BlueBubbles vs Linq