The Hook Model: How to Build Habit-Forming Products (Nir Eyal’s Framework Explained)

Why the Hook Model Matters

In today’s attention economy, successful products don’t just attract users—they create habits. Nir Eyal’s Hook Model (from his book Hooked) reveals how companies like Facebook, Instagram, and TikTok keep users coming back.

???? Key Insight: Products using the Hook Model see up to 3X higher user retention (Nir Eyal, 2024).

The 4 Stages of the Hook Model

1. Trigger (External & Internal)

What prompts the user to act?

• • External Triggers: Notifications, ads, emails (“Your order is shipping soon!”).

• • Internal Triggers: Emotions (boredom → open TikTok, stress → check Instagram).

???? Example:

Slack uses external triggers (unread message badges) and internal triggers (fear of missing out on updates).

2. Action (The Simplest Behavior)

The user takes a small, easy step.

• • Fogg Behavior Model: B = MAP (Behavior = Motivation + Ability + Prompt).

• • Reduce friction: 1-click purchases, auto-play videos.

???? Example:

Twitter’s infinite scroll removes friction, making it effortless to keep consuming content.

3. Variable Reward (The “Addictive” Part)

Users get unpredictable rewards, triggering dopamine.

• • Types of Rewards:
    
    • • Social (Likes, comments)
    • • Hunt (Gamification, streaks)
    • • Self (Mastery, progress bars)

???? Example:

LinkedIn’s “Who viewed your profile” feature creates curiosity (variable social reward).

4. Investment (Users Put Something In)

The more users invest (time, data, money), the likelier they return.

• • Examples:
    
    • • Customizing profiles (Instagram)
    • • Saving preferences (Netflix)
    • • Building streaks (Duolingo)

???? Example:

Pinterest users who create boards are 5X more likely to return (Nir Eyal, 2024).

How to Apply the Hook Model

For Apps & Digital Products

1. 1. Identify the user’s internal trigger (What emotional need does your product solve?).

1. 1. Simplify the action (Can they use it in <10 seconds?).

1. 1. Design rewards that vary (Surprise them!).

1. 1. Encourage small investments (Save, follow, customize).

???? Case Study:

Duolingo:

• • Trigger: Notification (“Your streak will break!”).

• • Action: 5-minute lesson.

• • Reward: XP, leaderboards, “Well done!” animations.

• • Investment: Streaks, unlocked levels.

For E-commerce & SaaS

• • Trigger: Abandoned cart emails.

• • Action: “Complete your purchase in 1 click.”

• • Reward: Limited-time discount (variable).

• • Investment: Loyalty points, saved payment methods.

Ethical Considerations

⚠️ Warning: The Hook Model can be manipulative. Nir Eyal later wrote Indistractable to address ethical design.

• • Do: Solve real problems.

• • Don’t: Exploit psychological vulnerabilities for addiction.

Key Takeaways

✔️ Hooks create habits—not one-time use.
✔️ Variable rewards are the most powerful stage.
✔️ Always align with user needs (not just business goals).

???? Want More? Read Hooked by Nir Eyal or our guide on The Psychology of Conversions.

Which apps “hook” you the most? ???? Comment below!