Spark vs Canary Mail on Mac: Free Tier vs Encrypted Inbox

Spark vs Canary Mail on Mac looks like a feature fight and is actually an architecture fight. Both run on macOS, both connect Gmail, Outlook, Exchange, iCloud and plain IMAP, both put an AI writing assistant in the composer, and both have a free tier. On a spec sheet they nearly overlap.

They differ on one thing that a spec sheet hides: what happens to the body of an email while the app is working on it. Spark is built to let mail pass through, and briefly rest on, Readdle's servers, because that is what shared drafts and link sharing require. Canary Mail is built around the opposite instinct — encrypt on send, index locally, hold as little as possible.

That single decision explains almost every other difference between them, including the ones that look unrelated. This comparison is judged on documented capability from each vendor's own pages as of September 2026, not on a bake-off we did not run.

The verdict up front#

If more than one person touches the inbox, use Spark. Shared drafts, in-thread private comments, assignments and shared inboxes are real collaboration features that Canary Mail does not match, and no amount of encryption compensates for a team that has to forward things to each other.

If the inbox is yours alone and the contents are sensitive — client files, patient records, deal documents, anything a regulator has an opinion about — use Canary Mail. It is the only one of the two that offers end-to-end encryption at all.

Everyone else, which is most people, should decide on the server question rather than the feature list. Spark's own privacy policy describes email content being processed in Spark systems where a feature requires it. Canary's positioning is that your provider stores the mail and Canary displays it locally. Neither is wrong; they are answers to different questions.

At a glance: Spark vs Canary Mail on macOS#

Where Spark wins#

Spark wins collaboration outright, and it is not close. Shared drafts let two people compose the same reply at the same time. Team Comments put a private conversation inside the thread instead of in a parallel Slack channel. Assignments give a message an owner and a deadline. Shared inboxes cover the support@ and info@ addresses that a small company actually runs on.

Canary Mail has team features, but they are AI routing and AI-drafted replies rather than co-authoring. If your workflow is "three of us answer the same mailbox and need to not double-reply," Spark is the answer and Canary is not.

Spark also wins on breadth of focus tooling. Smart Inbox, Priority, Gatekeeper for screening unknown senders, Set Aside, Snooze, Send Later, Smart Folders and a command centre add up to a client you can run a whole day in without leaving. The Apple Watch app is a small thing, but Canary does not have one.

• Shared drafts and real-time co-composition — no equivalent in Canary Mail
• Private in-thread comments, so triage discussion stays attached to the message
• Assignments with owner and deadline, plus read statuses across the team
• Shared inboxes for role addresses, with centralised team administration
• A deeper focus toolkit: Gatekeeper, Priority, Set Aside, Smart Folders, Command Center

Where Canary Mail wins#

Canary Mail wins encryption, and it wins it in the only way that counts: the feature exists. Spark offers no end-to-end encryption at all, so on this dimension there is no comparison to make.

Canary's PGP implementation is aimed at people who do not want to run a key ceremony. It describes encryption as activating on send, being OpenPGP compatible so recipients do not need Canary, and key management as optional for users who want it. That is a meaningfully lower bar than classic PGP tooling.

SecureSend is the more practically useful half. It is Canary's own mechanism for recipients who have no PGP at all: a password-protected, expiring message, positioned for healthcare, legal and finance, with HIPAA framing and a BAA available on request. Most real correspondence is with people who will never install a key, and that is the case SecureSend covers.

The security work around the edges is also stronger. Canary blocks tracking pixels by default, flags spoofed senders and impersonation attempts, and warns on misdirected recipients. Spark's security page is about infrastructure — encryption at rest, VPNs, code review — not about protecting you from the contents of a message.

The axis both vendors' marketing skips: where your mail rests#

Most Spark vs Canary Mail comparisons stop at the feature grid. The more useful question on a Mac is which machine holds the plaintext of a message while a feature runs, because that is what a security review will ask and what a client contract may forbid.

Spark answers this in writing. Its privacy policy states email content is mainly processed on your device but may also be processed in Spark systems when a feature requires it, and it names shared emails, shared drafts and send-later messages as examples. Its retention table lists recent emails as retained for four hours, with shared items, read statuses, AI history and writing-style samples kept until you delete them or close the account. Credentials are stored as a token the company says it cannot retrieve.

Canary's answer is the mirror image: your provider stores the mail, Canary syncs and displays it locally, and the company describes a zero-access model. That is a different trade, not a free win — it is also why Canary cannot offer live shared drafts. The server is what makes collaboration possible.

How the AI features actually compare#

On capability, Spark has more surface area. It ships a writing assistant for drafting, translating, summarising and proofreading, an AI Assistant that can search across mail, attachments and events, meeting-note transcription, a My Writing Style feature, and personalisation context you fill in about your role and schedule. Inbox automation — auto-drafts, auto-labels and workflows — is on its pricing page, with several items marked as coming rather than shipping.

Canary's set is narrower and more triage-shaped: an AI Copilot for drafting and tone rewriting, thread summaries, natural-language search across accounts, and AI prioritisation that splits newsletters and promotions out of the inbox.

The more decision-relevant difference is disclosure. Spark names its AI providers — Azure OpenAI, OpenAI, Claude and Vertex AI — says it may switch between them, states it does not train models on your data, and notes providers may retain inputs for up to 30 days for abuse monitoring. If you have to fill in a vendor questionnaire, that is answerable.

Pricing model: what shape each one is#

We do not print competitor prices, because they change and a stale number is worse than none. The shapes are worth knowing, though, because they differ more than the numbers do.

Spark runs Free, Plus, Pro and Enterprise for individuals, with a separate team pricing page, subscription billing, and a seven-day trial on the paid individual tiers when you subscribe in-app. Its free tier is unusually generous on accounts — unlimited mailboxes, smart notifications, calendar — and limited mainly on AI usage and advanced sharing.

Canary runs Free, Growth and Pro+, billed yearly or as a one-time lifetime purchase, with no monthly option at the time of writing. It also offers a seven-day trial of paid features without a card, dropping back to Free afterwards, and caps devices per tier. A lifetime option is rare in this category and it changes the maths if you intend to stay for years.

Check both on the vendor's own pricing page before buying. Tier contents move; the encryption-on-top-tier detail above is exactly the kind of thing that a review written a year ago gets wrong.

Who each one is genuinely for#

A third option, honestly#

We build AI Emaily, so treat this section as what it is: the case for our own product, stated with its limits attached.

AI Emaily is not the right answer if you came to this comparison for PGP. We do not offer end-to-end encrypted mail, and on that dimension Canary Mail beats us the same way it beats Spark. If encrypted send is the requirement, stop here and buy Canary.

Where we are a real third option is the part neither of these two is built around: an agent that triages and drafts across every connected mailbox and asks permission before it sends. Copilot mode means nothing leaves your account without your approval, every action is undoable, and the audit log records what the agent did and why. Voice comes from a Personal Context brain you write and per-client profiles you set, not from scraping your sent folder. We do not train models on your mail.

On the Mac specifically, be clear about what you are installing. AI Emaily ships a real downloadable Mac app — a proper app window, Dock presence, system notifications — built as an Electron shell around our web interface, Apple Silicon only, and not distributed through the Mac App Store. Features land on desktop the same day as web because it shares the codebase. It will not match a native AppKit client on memory footprint, deep OS integration, or a complete offline archive; reading and drafting work offline, full local archive does not. There is no permanent free tier — it is a seven-day free trial on Pro and Autopilot, card required, no charge if you cancel before day seven.

How to choose in five minutes#

1. 1

   Answer the team question first

   If two or more people work the same mailbox, Spark wins and the rest of this list is optional detail.

2. 2

   Answer the encryption question second

   If any message must be unreadable to the vendor in transit, Canary Mail is the only one of the two that does it. Confirm which tier carries PGP and SecureSend today.

3. 3

   Read Spark's retention table, not its marketing page

   The four-hour recent-email window and the longer retention on shared and AI items is the fact a security reviewer will ask about.

4. 4

   Trial both against your real accounts

   Both offer a seven-day window. Connect the messy account — the Exchange one, or the IMAP host nobody has heard of — not the clean Gmail.

5. 5

   Check the device cap before you pay

   Canary limits devices per tier. A Mac, an iPhone and an iPad is already three.