This comparison comes up because the two vendors sit at different ends of the same category and both rank for the same searches. The differences that matter are not in the feature lists.
At a glance
| Linq | Sendblue | |
|---|---|---|
| Positioning | Enterprise communications API | Developer-first iMessage API |
| Pricing | Not published — quote only | $100/month per dedicated line, published |
| Compliance stated | SOC 2 Type II, encrypted content | SOC 2 Type II, HIPAA support |
| SLA | 99.95% uptime, advertised as contractual | Not published |
| Documentation | Public reference | Public, with documented request shapes |
| Free access | Sandbox / trial | Free sandbox |
| Group chats | Listed | Check current docs |
| Beyond iMessage | RCS, SMS, voice | SMS and RCS fallback |
The real dividing line
Ask who has to sign off. If it is you and the deploy pipeline, published pricing and readable documentation are worth more than any certification, and Sendblue is the shorter path — sandbox to production without a sales conversation.
If it is a security reviewer, a procurement team and legal, then the artefacts are the product: a SOC 2 Type II report, a DPA, an SLA with a remedy clause. Linq's whole positioning is built around producing those, and both vendors state SOC 2 Type II — so ask both for the report and compare the scope and period rather than the marketing line. How to run that evaluation.
Neither certification changes the underlying fact
Apple publishes no iMessage API. Both vendors reach iMessage by means Apple has not sanctioned, and a SOC 2 report attests to a company's internal controls, not to Apple's permission. Any evaluation that treats a certification as resolving the channel risk has misread it. The structural position.
Cost, as far as it can be compared
Sendblue publishes $100 per dedicated line per month. Linq publishes nothing; competitor comparison pages put it around $250 per line plus a four-figure setup fee, which is a rival's characterisation and worth treating as an order of magnitude rather than a quote.
If that shape is roughly right, Linq is a multiple of Sendblue's price. Whether that is bad value depends entirely on whether the SLA and the report are unblocking a deal. For a five-person company they are not. For a regulated enterprise they may be the only reason the project happens at all.
Choosing
| If | Then |
|---|---|
| You want to ship this week | Sendblue |
| A security questionnaire is blocking you | Linq |
| You need group threads and FaceTime scheduling | Linq lists both — confirm in the sandbox |
| Budget is under $200/month | Sendblue, or cheaper still |
| You need one vendor for iMessage, RCS, SMS and voice | Linq |
| You want an inbox for non-technical staff | Neither — Miss Blue |
Both offer a way to send a real message before you commit. Do that before the sales call, in both cases — twenty minutes against the actual API is worth more than either vendor's comparison page, and worth more than this one.