\"cs-notification-strategy\"

Framework

IRON LAW: Every Notification Must Earn Its Send

Each notification interrupts the user. If it doesn't deliver clear value
to the RECIPIENT (not to your business), it erodes trust and drives
opt-outs. Before sending: "Would the user thank me for this notification?"
If no → don't send.

Channel Comparison

Channel	Open Rate	Speed	Cost	Best For	Limitations
Push notification	5-15%	Instant	Free	Time-sensitive, action-needed	Easy to opt out, limited text
Email	15-25%	Minutes	Low	Detailed content, receipts, newsletters	Spam filters, slow
SMS	90%+ open	Instant	$$$	Critical alerts, OTP, urgent	Expensive, intrusive, regulatory
In-app	25-40%	Next session	Free	Feature announcements, tips	Only reaches active users
LINE/Messenger	40-60%	Instant	Free-$	Conversational, Taiwan/Asia	Platform dependency

Timing Optimization

Audience	Best Time	Worst Time
B2C general	10-12 AM, 7-9 PM	12-6 AM, during commute
B2B	Tue-Thu 9-11 AM	Weekends, Friday PM
E-commerce	Thu-Sat (pre-weekend shopping)	Monday AM
Breaking/urgent	Immediately	N/A

Timezone rule: Send in the RECIPIENT's timezone, not yours.

Personalization Tiers

Tier	What	Example	Lift vs Generic
None	Same message to all	"Check out our sale!"	Baseline
Segment	By user group	"As a premium member, you get early access"	+20-30%
Behavioral	Based on past actions	"The item in your cart is almost sold out"	+40-60%
Individual	1:1 personalized	"Hi [Name], your favorite [Product] is back in stock"	+60-80%

Fatigue Management

Signal	What It Means	Action
Open rate declining	Content losing relevance	Improve targeting/content
Opt-out rate > 0.5%/send	Sending too much or wrong content	Reduce frequency, segment better
Uninstall spike after push	Notifications are driving users away	Immediately reduce volume
Click rate declining but open rate stable	Subject lines good, content disappointing	Improve content/offer quality

Frequency caps: Set maximum notifications per user per time period:

• Push: max 3-5/week
• Email: max 2-3/week (marketing), unlimited for transactional
• SMS: max 2-4/month

A/B Testing for Notifications

Element	What to Test	Example
Subject/title	Length, tone, emoji, personalization	"Your order shipped 📦" vs "Order #1234 is on its way"
Timing	Hour of day, day of week	10 AM vs 7 PM
Content	Short vs detailed, image vs text-only	20 words vs 50 words
CTA	Button text, action type	"View" vs "Track Now"
Channel	Push vs email vs in-app for same message	Same content, different channel

Output Format

# Notification Strategy: {Product/Campaign}

## Channel Mix
| Message Type | Primary Channel | Fallback | Frequency |
|-------------|----------------|----------|-----------|
| {type} | {channel} | {backup} | {max/period} |

## Segmentation
| Segment | Notification | Personalization Tier |
|---------|-------------|---------------------|
| {segment} | {content} | None/Segment/Behavioral/Individual |

## Timing
| Segment | Send Time | Day | Timezone |
|---------|----------|-----|---------|
| {segment} | {HH:MM} | {day(s)} | {user's TZ} |

## Fatigue Rules
- Max push: {N}/week
- Max email: {N}/week
- Opt-out threshold: {%} → action: {reduce/pause}

## A/B Test Plan
| Test | Variant A | Variant B | Metric | Sample |
|------|----------|----------|--------|--------|
| {test} | {A} | {B} | {open rate / CTR} | {N users} |

Gotchas

• Permission is a privilege: iOS requires explicit opt-in for push. Ask at the RIGHT moment (after the user sees value), not at first launch. First-launch permission requests get 40-60% opt-in; contextual requests get 70-80%.
• Transactional vs marketing: Order confirmations, shipping updates, and security alerts are transactional (expected, high open rate). Marketing promotions are interruptive (optional, lower open rate). Never mix them in user perception.
• LINE in Taiwan is unique: LINE has 95% penetration in Taiwan. LINE Official Account messages have 60%+ open rates — significantly higher than email or push. Prioritize LINE for Taiwan audiences.
• Rich push is underused: Push notifications can include images, action buttons, and deep links. A rich push with "View Order" button converts 3-5x better than a text-only push.

References

• For LINE notification setup, see references/line-notification.md
• For email deliverability optimization, see references/email-deliverability.md