Guest Blogger Hannah H.

What Makes An App Stick

There are nearly 5 million apps available across the App Store and Google Play. But despite all of these choices, 25% of apps are opened only once after being downloaded and then never again.

So, why are so many apps being neglected? And what makes other apps part of our daily lives?

The answer lies in understanding human behavior. Every design feature should be developed with careful consideration of why users do what they do, what motivates them to return, and how to create experiences that feel rewarding, not draining.

This article explores the behavioral science behind app engagement, from fundamental models to real-world examples. Psychology of engagement is key to creating an app that people want to use and continue coming back to.
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The Science Behind Engaging Apps

Behavioral design frameworks help developers understand their audience better and reduce friction. BJ Fogg’s Behavior Model ensures each individual action is well-designed. Then, layer Nir Eyal’s Hook Model on top to create a cycle that turns actions into habits. Let’s break down these models individually so you can see how they work and apply them to your own designs.
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Fogg’s Behavior Model

The Fogg Behavior Model says that for a behavior (B) to occur, three things must happen at the same time: motivation (M), ability (A), and a prompt (P). Oftentimes, you’ll see this model summarized as B=MAP.

Motivation: This component refers to the user’s desire to perform the behavior. Fogg breaks this down into sensation (pleasure or pain), anticipation (hope or fear), and belonging (acceptance or rejection).
Ability: This component is all about how easy it is for a user to complete the behavior. The easier the action is, the more likely it will happen, even if motivation is low.
Prompt: This element is the trigger that starts the behavior. Without a prompt, the target action will hardly be completed, even with highly motivated and capable users.

Take Duolingo’s streak system as a prime example. Every day, users receive an alert (prompt) to complete their lesson and maintain their streak. Even if motivation is low, Duolingo makes it very easy to complete the action (ability) and offers a streak-freeze when users finish multiple lessons.
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Nir Eyal’s Hook Model

Another behavioral design concept used in app development is Eyal’s Hook Model. It describes a four-step cycle that turns user engagement into habitual behavior.

Trigger: Similar to Fogg’s prompt concept, a trigger is a cue for a user to use the product. It could be a notification (an internal trigger) or it could be the feeling of plain boredom (an external trigger).
Action: Eyal combined motivation and ability to come to a product’s desired action. This could be opening an app or scrolling through a feed.
Variable Award: Everyone likes to be rewarded for their actions, and adding a mix of variability increases dopamine levels and keeps users coming back.
Investment: Users are more likely to return when they invest their time, effort, or data into the product.

For example, when you see content that resonates with you on Instagram, you’re likely to follow that account (investment), which keeps you engaged. You come back later to see new content (trigger → action), and each scroll reveals something new (variable reward).
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Designing for Emotion: Strava Example

After users establish motivation and take action, building emotional resonance helps create a bond between users and the app. This makes the user experience more meaningful and drives higher engagement. Apps can drive this emotional connection through achievement and community belonging.

Consider Strava’s model as an example. Users earn badges for reaching new personal activity records (running, biking, etc.) or surpassing a distance goal. Progress bars show how close you are to a specific mark and leaderboards show how you stack up with friends, as well as by age and gender.

In terms of community engagement, every activity you complete can be shared with your feed, allowing others to give “Kudos” and positive comments. The platform also supports route sharing so users can see where others have explored and perform the same trail.

According to Strava’s 2025 mid-year data, run clubs on the app have tripled since last year and 55% of Gen Z athletes say that social connection is their main motivator for joining a fitness group.
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UX and Design Elements to Elicit Emotion

Users form habits around how apps make them feel. These design choices can help evoke emotion:

Tone of voice: Normally (depending on the type of app), a conversational and positive tone helps users reduce anxiety and build trust.
Color: Evidence shows that warm colors (red and yellow) create excitement or urgency, while cool colors (blue and green) convey calm and trust.
Micro-interactions: Small animations and feedback moments, such as a “like” heart bursting, or confetti when completing a task, create a sense of accomplishment and joy.
Brand personality: Humanizing the app through storytelling, mascots, or a distinct personality also helps build emotional connection.
Visual progress and rewards: Showing progress visually, like avatars leveling up or badges earned, can provide users with motivation and pride.
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Tips for Developers Building Habit-Forming Apps

Designing apps that are habit-forming, not addictive, is an important distinction for maintaining user trust and ethical integrity. Overall, users’ long-term trust outweighs short-term dopamine hits.

Here are some practical tips for forming healthy habits and fostering meaningful engagement:

Start with intrinsic motivation: Identify genuine user needs, goals, and values to design features that resonate emotionally and purposefully.
Create feedback loops: Use clear and immediate feedback and micro-interactions that give users a sense of progress, without overwhelming them.
Use personalization thoughtfully: Respect user privacy and support engagement by allowing users to customize features and experiences.
Test emotions and UI flows: Test emotional impact, tone, and resonance as much as usability. Use empathy-driven research (interviews, open-ended feedback) to capture motivations and frustrations.
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Psychology in App Design

The best apps are not made to manipulate user's attention. The ones that stick are the apps that help us grow, learn, or connect in meaningful ways.

Every element plays a rule in turning a single action into a lasting habit. We see that through Fogg’s Behavior Model, Eyal’s Hook Cycle, and emotional design principles that foster connection and keep users engaged for the long run.

Lithios can help your brand build lasting engagement through thoughtful app design. We blend behavioral insight with experienced app development to help your product resonate with your target audience.