One account. Any number of devices and agents. Each with its own email address.
Mailcycle is programmable, privacy-first email infrastructure. The same product runs a single private address on your phone, an inbox for your AI agent, or a console provisioning addresses across a thousand devices. Here is how it fits together.
One place to manage every device and email address.
An Operator controls the Mailcycle environment: devices, email addresses, assignments, plans, usage and account settings. It works from a phone to a wide desktop, with the same screens on both.
Home
Your email addresses, devices and mail this week, the latest mail and your devices at a glance.
Email addresses
Every address on your account and how many your plan allows. Create addresses, read their mail, see which device holds each one, and delete addresses to free their place.
Devices
Search by name, ID, tag or address, filter by status or tag, sort, and on Operator and above select many to disable, enable or remove at once.
Device detail
Rename, tag and add notes, assign or remove email addresses, read the device's mail remotely, disable it for a while or remove it.
AI agents
Connect an agent by pasting the line its MCP server prints, give it addresses, and choose whether it can send: reply only, to anyone, or not at all.
Plans & Billing
Plan, address limit and payment. On the web, pay by card or crypto, or top up a balance from $15 and the plan takes its price from it each month, before any card is charged. Downgrades are checked against the addresses you hold before they are accepted.
Your domains
On Scale and above, bring your own domains: prove ownership with a DNS record, and Mailcycle checks each step against public DNS.
API
A map of the HTTP API the app itself runs on: where it lives, how to get a session, and every route an account token can call. Your API keys, what each has been used for, and when each was last used.
Usage and events
What you have used against what your plan allows, and a log of account events: an address created, a device paired, mail sent. The same figures are on the API.
Settings and support
Account details, security (signed-in sessions, app lock on phones, sign out when inactive on the web), appearance, notifications, data export and account deletion. Support requests are encrypted on your device, so only you and our support team can read them.
Scan. Connect. Assign.
A Worker is a connected device or browser that receives mail for one or more Mailcycle email addresses. It has no account or password, and sees only the addresses assigned to it.
- Opens its own mail with the keys it was given: inbox, sent, junk, trash and starred
- Holds its own credential, kept in the phone's secure storage
- Survives restarts without re-pairing
- Writes, replies and forwards from its own addresses on Personal and above, and from nothing else. Drafts stay on the device
- Hears at once when it is removed, or an address is assigned to it or taken off it
- Cannot list other devices, mint email addresses or reach billing
- Can be disabled or removed from the console at any time
- Runs in a browser where an app cannot be installed
How a device joins an account
Worker device
Opens Mailcycle, shows a code
QR or pairing code
Scanned or typed, single use
Operator
Confirms the device on the account
Address assigned
One address, or several
Ready
Mail arrives on the device
The device shows an 8-digit code and a QR code. You scan or type it in the console and confirm the device, and a credential scoped to that one device is minted. A code works once, and an unclaimed code is cleared after 14 days. Assign an email address and the device starts receiving mail.
A Worker without a screen.
An AI agent pairs like a device, holds keys only for the addresses you give it, and reads and replies through MCP. It decrypts on the machine it runs on, and starts able only to answer whoever wrote to it.
- Paired by pasting one line, so its keys never pass through us
- Waits for, reads and replies to mail, and opens and sends files, through seven MCP tools
- Reply only, send to anyone, or read only, set per agent
- Sends from the addresses you give it, up to 20 messages an hour, more on Fleet and Enterprise
- Shows as online in the console while it runs
- Removed or disabled from the console like any device
Addresses are a resource you distribute.
A plan sets how many email addresses your account can hold, not how many devices it can pair. Devices are unlimited on every paid plan, and Free pairs one. Every address you create counts, assigned or not, and deleting one frees its place. Deleted addresses are retired and never reissued to anyone.
| Example fleet on Scale (1,000 addresses) | Email addresses | Counted toward plan |
|---|---|---|
| iPhone Rack A-12 | 1 | 1 |
| Testing Pixel 07 | 3 | 4 |
| Browser Worker 04 | 1 | 5 |
| Remaining | 995 more addresses available | |
Downgrades are checked first. If you hold 340 email addresses and try to move to a plan that allows 250, the change is refused and tells you how many to delete first. Nothing is deleted for you.
Both ends of the handshake see the same thing.
Every change is recorded as an event and shown at once on every open screen on the account. A paired device hears straight away when it is removed, an address is assigned to it or taken off it, or mail arrives.
Device events
- worker.paired
- worker.connected
- worker.disconnected
- worker.removed
Address events
- inbox.created
- inbox.assigned
- inbox.removed
- inbox.deleted
Mail and billing
- message.received
- message.sent
- subscription.updated
Your code can have them too. From Operator, webhooks POST these events to a URL you choose, signed and retried, and an API key can hear them over the event stream. They carry ids, never content. See the docs.
Three platforms, one product.
Mailcycle is the same product on iOS, Android and the web. There is no "lite" version. The web app works today, on phones too; the iOS and Android apps are coming soon to the stores.
iOS
Native app with camera QR pairing and credentials in the Keychain. iPhone and iPad, including tablet layouts.
App Store: coming soonAndroid
Native app with camera QR pairing and credentials in the Keystore. Edge-to-edge and themed icons supported.
Google Play: coming soonWeb
The full console and the full device interface in any modern browser. Pairing scans a QR code with a webcam, or takes the 8-digit code by hand.
Open the appCreate your first email address.
Free to start, no card, three email addresses to try it with. Pair a device whenever you like.