Communication Channels Overview

How you reach users — push, email, SMS, and more — and how channel preferences work in Zixflow. Available today: Mobile push notifications (iOS / Android). Other channels are planned; opt-out fields already exist on profiles so you can store consent early.

What Are Communication Channels?

A channel is a pathway for outbound messages:

Channel	Best for
Push	Urgent, short alerts on mobile
Email	Rich content, newsletters, receipts
SMS	Critical, high-urgency short messages
In-app	Guidance while the app is open
Web push	Browser alerts for web users
WhatsApp / RCS	Conversational messaging (where available)

Different channels trade off reach, speed, visibility, cost, and content richness. Use the channel that matches urgency and message complexity.

Channel Opt-Out Model

Every profile stores opt-out status per channel:

Status	Value	Meaning
`NOT_OPTED_OUT`	1	Reachable (default for Push, SMS, WhatsApp, RCS)
`OPTED_OUT`	2	Explicitly opted out — sends suppressed
`UNKNOWN`	3	Intent not established (default for Email)

Each channel also has an _opt_out_at timestamp.

Zixflow.instance.setProfileAttributes({
  'sms_opt_out': 2,
  'sms_opt_out_at': DateTime.now().toIso8601String(),
});

Zixflow.instance.setProfileAttributes({
  'push_opt_out': 1, // NOT_OPTED_OUT
});

User Suppression blocks all channels at once (server-side lifecycle events User Suppressed / User Unsuppressed). See User Preferences & Consent.

Push Notifications (Available)

Platform: iOS, Android
Delivery: APNs / FCM
Latency: Typically under 5 seconds
Opt-in: System permission dialog
Opt-out field: push_opt_out (default NOT_OPTED_OUT) Supported today:

Device token registration and multi-device profiles
Platform routing (iOS → APNs, Android → FCM)
Profile push_opt_out / push_opt_out_at
Deep linking
Delivery / open / action tracking — Push Notification Tracking

When to use: Order updates, payment failures, cart reminders, real-time alerts. Setup guides: Devices & Push and the SDK push docs.

Coming Soon

These channels are not live for delivery yet. Opt-out fields are already on the profile so you can capture consent ahead of launch:

Channel	Opt-out fields	Notes
Email	`email_opt_out` / `email_opt_out_at`	Default `UNKNOWN` until confirmation
SMS	`sms_opt_out` / `sms_opt_out_at`	Default `NOT_OPTED_OUT`
WhatsApp	`whatsapp_opt_out` / `whatsapp_opt_out_at`	Default `NOT_OPTED_OUT`
RCS	`rcs_opt_out` / `rcs_opt_out_at`	Default `NOT_OPTED_OUT`
In-app messages	—	Rendered in-app when available
Web push	—	Browser Push API

Choosing a Channel (Pattern)

Ask:

How urgent? Critical → Push or SMS · Important but not urgent → Email · Contextual → In-app
How much detail? Quick alert → Push/SMS · Long explanation → Email · Interactive → In-app
Where is the user? In app → In-app · Away → Push/Email

Example: Cart recovery (orchestration pattern)

This is a common multi-channel pattern. Today you can implement the push steps; email/SMS steps apply when those channels ship.

Use case	Primary	Backup
Order shipped	Push	Email
Cart abandoned (2h)	Push	Email
Cart abandoned (24h)	Email	Push
Password reset	Email + Push	SMS
Weekly newsletter	Email	—
Flash sale	Push	SMS
Feature tip	In-app	Push
Payment failed	Email	Push

Push Best Practices

Do: Request permission after showing value; personalize; clear CTA + deep link; respect quiet hours. Don’t: Ask on first launch; send generic spam; ignore opt-outs or quiet hours.

Next: User Preferences & Consent

​What Are Communication Channels?

​Channel Opt-Out Model

​Push Notifications (Available)

​Coming Soon

​Choosing a Channel (Pattern)

​Example: Cart recovery (orchestration pattern)

​Push Best Practices