Lifecycle email and push from in-app events (without a separate CRM sync)

The default lifecycle stack looks like this: product analytics in one tool, user lists in Customer.io or Braze, and a nightly CSV or Zapier job that tries to keep trial_started in sync with last_seen_at. It works until it does not: duplicate profiles, six-hour lag, and automations that fire after the user already converted.

Subscription teams feel this most on behavioral triggers: stalled onboarding, paywall abandon, trial day three with no core action. Those signals live in the app now. They should not wait for a warehouse export.

Rheo Engage runs lifecycle email, push, and webhooks from the same SDK events and segments that power Analytics and Convert. No separate CRM sync is required for the common case: define the segment on journey behavior, attach the automation, respect marketing consent. This post explains the model, channels, and how it complements RevenueCat: not replaces your billing source of truth.

Why CRM sync breaks on mobile subscription apps

Sync pattern	Failure mode
Nightly warehouse → CRM	User converts at 9am; email at 9pm says "finish trial"
Duplicate identities	Anonymous install vs email account
Property drift	trial_end in CRM ≠ RevenueCat
Engineering bottleneck	Every new trigger needs ETL

Event-triggered lifecycle flips the direction: the app (and server hooks) emit facts; Engage reacts.

The Rheo model: events → segments → automations

1. SDK events: onboarding_step_completed, paywall_viewed, feature_used, custom milestones.
2. Segments: rules like "completed step 1-2 but not 3 within 48h" or "trial active AND no core_action."
3. Engage automations: enter segment → send email / push / webhook → exit on conversion or timeout.
4. Revenue hooks: optional RevenueCat webhooks to align subscription_status on the profile.

Segments update from live behavior, not yesterday's batch.

Channels: email, push, webhooks

Email

Best for narrative, links to web checkout, and users who disabled push. Use for:

• Trial education sequences branched on in-app progress
• Win-back after voluntary cancel (paired with in-app: see email vs in-app win-back)
• Payment failed instructions with clear CTA

Configure templates in Rheo; track opens/clicks where supported. Suppress sends when marketing consent is off.

Push

Best for time-sensitive nudges: "Finish setup," "Trial ends tomorrow." Requires OS permission; treat promotional pushes as marketing consent in regulated markets.

Pair push with in-app Convert flows: push opens app → remote onboarding or paywall variant loads without release.

Webhooks

Best for ops and mixed stacks:

• Slack alert when high-LTV user hits cancel flow
• Enrich Zendesk when user files bug after NPS detractor score
• Fan-out to data warehouse if finance wants a copy

Webhooks fire on the same triggers as email: useful when legal wants email in one system but product events stay in Rheo.

Channel	Latency	Reach after uninstall	Rich UI
Email	Minutes	Yes (if address)	Low
Push	Seconds	No	Notification only
Webhook	Seconds	N/A	Your handler
In-app (Convert)	Instant on open	No	High

Engage plus Convert covers notify and show without a CRM sync.

Example automations (no sync required)

Trigger (event / segment)	Email	Push	Webhook
paywall_viewed + no trial_started 24h	Value recap	Short nudge	:
Onboarding stall step 3	Tips email	"Pick up where you left off"	:
trial_started + no aha_event 72h	Feature guide	Feature highlight	CS Slack
RC CANCELLATION + reason price	Offer email	:	CRM note
payment_failed	Update card link	Urgent banner	Billing queue

RevenueCat remains authoritative for billing; Rheo reacts to webhook-enriched profile state and in-app behavior in one place.

Compared to Customer.io / Braze

Approach	CRM-led (Customer.io, Braze)	Event-triggered Engage on Rheo
Profile source	Imported users + attributes	SDK + optional RC webhooks
Behavioral triggers	Needs sync or API calls	Native segments on events
In-app flows	Deep links; limited remote UI	Shared Convert flows
Best when	Mature marketing org, many channels	Events already in Rheo SDK

Many teams keep Customer.io for newsletter-grade programs and use Rheo Engage for product-native triggers: not because one must win, but because sync cost hurts most on real-time behavior.

Implementation checklist

1. Instrument milestones: same events for Analytics funnels and Engage segments.
2. Identity: merge anonymous → account early so automations do not double-send.
3. Marketing consent: gate promotional email/push; see consent-first analytics.
4. Exit conditions: always define "user converted" to leave the journey (trial_started, subscription_active).
5. Rate limits: cap emails per week; churned users need fewer touches, not more.
6. Test users: dashboard preview to a segment of internal accounts.

Honest limits

• Engage is not a full CDP for every ad network and SMS vendor at enterprise scale.
• Complex branching across twelve channels may still belong in Braze if you already pay for implementation depth.
• Transactional email (password reset) should stay on your auth provider.

Where Rheo fits: subscription apps that already ship Convert flows and want lifecycle on the same events without a nightly job.

Stack picture

Layer	Tool examples
Billing	RevenueCat, Stripe
Paywalls	Superwall
Analytics (optional second tool)	PostHog, Mixpanel
Journeys + lifecycle	Rheo Convert + Engage

Debugging automations that feel "late" or "wrong"

When a lifecycle message misfires, the bug is usually identity or exit rules: not the template.

Symptom	Likely cause	Fix
Email after user already subscribed	Exit event not wired from RC webhook	Add subscription_active exit on webhook
Duplicate emails	Anonymous + identified profiles	Merge on signup; dedupe segment
Push never sends	Marketing consent false or no token	Check consent flag and FCM/APNs registration
Webhook storms	Retry without idempotency key	Hash user_id + automation_id + day
Segment always empty	Event name typo vs dashboard	Align SDK event catalog with Engage rules

Log a single automation_decision event in development (entered, suppressed_consent, exited_converted) so support can trace one user without reading raw queues.

Rolling out without spamming your best users

Ship lifecycle in layers:

1. Internal accounts only for 48 hours.
2. 5% of new trials for onboarding automations.
3. Full rollout after unsubscribe rate stays flat week over week.

Keep a global frequency cap: no more than three promotional emails and two promotional pushes per rolling seven days unless the user is in payment-failed utility mode.

Engage sits closest to Convert in the stack because both read the same behavioral stream: billing and paywalls stay in RevenueCat and Superwall.

Start for free and attach your first Engage automation to an in-app segment: email, push, or webhook: from the dashboard.