iCloud API
iCloud Mail, Calendar and Contacts with an app-specific password
iCloud
How an account links
- IMAP/SMTP
- CalDAV/CardDAV
- emailList mail · Send mail · Drafts · Folders and labels · Threading · Attachments6
- calendarCalendars · Events · Availability3
- contactsContacts · Contact search2
- platformWebhooks1
What Aux0 does with iCloud
12 capabilitiesiCloud Mail, Calendar and Contacts with an app-specific password
Connect an iCloud account with an app-specific password generated in Apple's account settings. Mail arrives through the same unified endpoints as Gmail and Outlook, and the account's calendars and contacts come with it.
- List mailPage through messages with search, label and date filters.
GET /v1/emails - Send mailSend a message, reply in thread, or forward one.
POST /v1/emails - DraftsCreate, update and delete drafts in the user's own mailbox.
POST /v1/emails/drafts - Folders and labelsList folders, and move or label a message.
GET /v1/folders - ThreadingGroup messages into threads with a stable thread id.
GET /v1/emails?thread_id= - AttachmentsUpload outbound attachments and fetch inbound ones.
GET /v1/emails/:id/attachments/:attachmentId
Calendar
- CalendarsList the calendars the account can read or write.
GET /v1/calendars - EventsCreate, update, move and cancel events, with attendees.
POST /v1/calendars/:id/events - AvailabilityRead free/busy across calendars to offer meeting slots.
POST /v1/calendars/availability
Contacts
- ContactsPage through the contacts on the account, with addresses and phones.
GET /v1/contacts - Contact searchLook up a contact by name or address, for autocomplete.
GET /v1/contacts/search
Platform
- WebhooksSigned delivery of every event, with replay and a dead letter queue.
POST /v1/webhooks
How an account is linked
AuthIMAP/SMTP
Host, port and credentials for a mail server. For self-hosted mail, regional providers and the long tail that will never ship an OAuth app.
CalDAV/CardDAV
Whichever method a provider uses, your users complete it on a page Aux0 serves under your branding. You receive an account id and a webhook; no password, QR scan or one-time code ever reaches your product. How hosted auth works.
What it is bought for
Use casesConsumer and prosumer users who live in Apple Mail
Founders and small teams on an iCloud custom domain
What you should know first
LimitsThe constraints, before you commit
These are the provider's rules, not ours. We would rather you read them now than discover one in production.
Apple issues no OAuth for mail, so the link uses an app-specific password.
Apple caps active app-specific passwords at 25 per account and revokes all of them when the Apple Account password changes, so Aux0 surfaces the account as needing reconnection.
iCloud does not support POP.
Next
RelatedConnect iCloud on the free plan
One connected account, every provider, forever. It is enough to build the whole integration before you pay for anything.