Zero to App Store: Designing quso.ai App Experience from Scratch

In this case study, I’ll walk you through the design and development of Captions & Subtitles — a mobile app designed to make AI-driven captioning simple and accessible. Initially launched as a focused MVP to test the waters, this app helped shape the future direction for Quso’s mobile strategy. From user research to iterative design decisions, discover how we brought AI-powered captions to life and validated product-market fit in just a month.

Context

quso.ai’s web platform offers a suite of AI tools for creators, including AI Clips, Captions, Influencer Avatars, and content planning. The original idea was to bring all of this into a mobile app. However, as we began scoping, it became clear that building a full-featured mobile version would take months, and we’d be guessing what mobile users needed. So we made a call:

Let’s launch one feature first — fast, focused, and built to learn.

That’s how Captions & Subtitles was born: a lightweight mobile MVP that lets users upload a video and instantly generate styled captions with AI. I led the end-to-end product design — from early exploration and UX flows to high-fidelity UI and paywall experiments. This case study explores how we transformed a narrow scope into meaningful insights and laid the groundwork for quso's mobile future.

At quso.ai, I worked as the sole product designer on the iOS app, driving the design process end-to-end—from ideation and user flows to high-fidelity designs and handoff.

On the web platform, I contributed to revamp the video editor, improving its usability and visual clarity for a smoother content creation experience. I also worked closely with product and engineering to design AI-powered features like AI Clips, focusing on integrating generative AI in a way that felt seamless and intuitive to users.

At quso.ai, I worked as the sole product designer on the iOS app, driving the design process end-to-end—from ideation and user flows to high-fidelity designs and handoff.

Project Scope

Will creators find value in AI-generated captions on mobile?

To get there, we designed a focused experience that did one thing really well — let users upload a video and generate shareable captions in seconds. But we also layered in just enough functionality to test real user behavior and readiness to pay.

At quso.ai, I worked as the sole product designer on the iOS app, driving the design process end-to-end—from ideation and user flows to high-fidelity designs and handoff.

Research & Product Insights

Web learnings guided every mobile decision

Since Quso’s web platform was already live, we didn’t start from zero. I had the opportunity to interact directly with web users, from individual creators to agencies managing multiple clients, and their feedback shaped much of our mobile strategy.

Individual creators mostly shoot and edit on their phones. For them, a mobile app would make posting faster and simpler. Agencies and high-scale creators preferred the web, where they already manage desktop workflows or repurpose content from YouTube. Many users just wanted fast, good-looking captions without spending time tweaking every detail. The idea of a mobile app was received positively across the board, especially by solo creators who valued on-the-go access.

These insights pushed us to keep the app lean, fast, and focused on creation, not configuration.

At quso.ai, I worked as the sole product designer on the iOS app, driving the design process end-to-end—from ideation and user flows to high-fidelity designs and handoff.

Design Process

Home Screen Interation 1

Our original scope included launching all core features from quso in a single mobile app. The home screen was designed to act less like a dashboard and more like a content hub.

There wasn’t a traditional “home” screen. Instead:

A CTA button Create (placed at the top) opened a creation sheet with all three feature options for new users
Existing users would land directly on their projects
The tab bar had three sections: Projects, Create, and Profile

This exploration helped us confirm that we’d move forward with launching three features — AI Clips, Captions, and Influencers. We decided the next version should mirror the web experience, so existing users would have less guesswork and a smoother transition.

Iteration 1

Our original scope included launching all core features from quso in a single mobile app. The home screen was designed to act less like a dashboard and more like a content hub.

There wasn’t a traditional “home” screen. Instead:

A CTA button Create (placed at the top) opened a creation sheet with all three feature options for new users

Existing users would land directly on their projects

The tab bar had three sections: Projects, Create, and Profile

Iteration 1

Our original scope included launching all core features from quso in a single mobile app. The home screen was designed to act less like a dashboard and more like a content hub.

There wasn’t a traditional “home” screen. Instead:

A CTA button Create (placed at the top) opened a creation sheet with all three feature options for new users

Existing users would land directly on their projects

The tab bar had three sections: Projects, Create, and Profile

Home Screen Iteration 2

After deciding to launch three features, we shifted our focus to make the app feel more like the web platform, especially for returning users who were already familiar with its structure.

This version of the home screen leaned into consistency:

A structured layout similar to a web, with clear cards for each feature.
These cards opened a bottom sheet to choose between upload and record video options.
Tabs at the bottom changed to Home, Projects, and Profile.

The goal here was to reduce the learning curve and make cross-platform usage feel seamless.

Iteration 2

After deciding to launch three features, we shifted our focus to make the app feel more like the web platform, especially for returning users who were already familiar with its structure.

This version of the home screen leaned into consistency:

A structured layout similar to a web, with clear cards for each feature.

These cards opened a bottom sheet to choose between upload and record video options.

Tabs at the bottom changed to Home, Projects, and Profile.

The goal here was to reduce the learning curve and make cross-platform usage feel seamless.

Iteration 2

After deciding to launch three features, we shifted our focus to make the app feel more like the web platform, especially for returning users who were already familiar with its structure.

This version of the home screen leaned into consistency:

A structured layout similar to a web, with clear cards for each feature.

These cards opened a bottom sheet to choose between upload and record video options.

Tabs at the bottom changed to Home, Projects, and Profile.

The goal here was to reduce the learning curve and make cross-platform usage feel seamless.

Home Screen Iteration 3

At this stage, we made two major shifts:

We decided to launch only AI Captions and not all three features
We launched it as a separate, lowkey MVP under the name "Captions & Subtitles" — not under the quso brand

With this narrowed scope, the home screen needed to reflect the product’s new focus: fast, single-purpose caption generation.

For new users, the home screen was clean and minimal, keeping the focus on getting started quickly.
No tab bar, no navigation-heavy layout.
Floating "Create" button as the primary action.
User projects appear directly on the home screen, making reuse and re-exports easy.

Iteration 3

At this stage, we made two major shifts:

We decided to launch only AI Captions and not all three features

We launched it as a separate, lowkey MVP under the name "Captions & Subtitles" — not under the quso brand

With this narrowed scope, the home screen needed to reflect the product’s new focus: fast, single-purpose caption generation.

For new users, the home screen was clean and minimal, keeping the focus on getting started quickly.

No tab bar, no navigation-heavy layout.

Floating "Create" button as the primary action.

User projects appear directly on the home screen, making reuse and re-exports easy.

Iteration 3

At this stage, we made two major shifts:

We decided to launch only AI Captions and not all three features

We launched it as a separate, lowkey MVP under the name "Captions & Subtitles" — not under the quso brand

With this narrowed scope, the home screen needed to reflect the product’s new focus: fast, single-purpose caption generation.

For new users, the home screen was clean and minimal, keeping the focus on getting started quickly.

No tab bar, no navigation-heavy layout.

Floating "Create" button as the primary action.

User projects appear directly on the home screen, making reuse and re-exports easy.

AI Captions

The entire flow was built to feel fast, focused, and mobile-first. Tapping the floating "Create" button opened a bottom sheet with two options: upload from the gallery or record directly. Once a video was selected, users landed on a preview screen with an optional language selector, a trim button, and a clear call to action: "Generate Captions". After that, a short animated loading screen bridged the wait while captions were processed in seconds. The goal was to keep everything light, smooth, and actionable, from input to output, with as little friction as possible.

Iteration 2

After deciding to launch three features, we shifted our focus to make the app feel more like the web platform, especially for returning users who were already familiar with its structure.

This version of the home screen leaned into consistency:

A structured layout similar to a web, with clear cards for each feature.

These cards opened a bottom sheet to choose between upload and record video options.

Tabs at the bottom changed to Home, Projects, and Profile.

The goal here was to reduce the learning curve and make cross-platform usage feel seamless.

Iteration 2

After deciding to launch three features, we shifted our focus to make the app feel more like the web platform, especially for returning users who were already familiar with its structure.

This version of the home screen leaned into consistency:

A structured layout similar to a web, with clear cards for each feature.

These cards opened a bottom sheet to choose between upload and record video options.

Tabs at the bottom changed to Home, Projects, and Profile.

The goal here was to reduce the learning curve and make cross-platform usage feel seamless.

Editor

Once captions are generated, users land in an editor that’s flexible but focused. We broke down the editing tools into intuitive tabs — Edit, Templates, Styles. Creators could tweak their content without feeling buried in options.

From bold animations to subtle typography shifts, every setting was just a tap away. The goal? Let users feel in control without needing a tutorial. By keeping the interface lightweight and scroll-friendly, we turned what could’ve been a complex captioning workflow into a fun, creative playground.

Iteration 3

At this stage, we made two major shifts:

We decided to launch only AI Captions and not all three features

We launched it as a separate, lowkey MVP under the name "Captions & Subtitles" — not under the quso brand

With this narrowed scope, the home screen needed to reflect the product’s new focus: fast, single-purpose caption generation.

For new users, the home screen was clean and minimal, keeping the focus on getting started quickly.

No tab bar, no navigation-heavy layout.

Floating "Create" button as the primary action.

User projects appear directly on the home screen, making reuse and re-exports easy.

Iteration 3

At this stage, we made two major shifts:

We decided to launch only AI Captions and not all three features

We launched it as a separate, lowkey MVP under the name "Captions & Subtitles" — not under the quso brand

With this narrowed scope, the home screen needed to reflect the product’s new focus: fast, single-purpose caption generation.

For new users, the home screen was clean and minimal, keeping the focus on getting started quickly.

No tab bar, no navigation-heavy layout.

Floating "Create" button as the primary action.

User projects appear directly on the home screen, making reuse and re-exports easy.

Export

After editing, users moved to a preview screen styled like an Instagram Reel, helping them visualise how the final video would look on social. Export options were clear and upfront: users could download a free version with a watermark or upgrade for 1080p and watermark-free output. Once they hit export, they were redirected to the home screen where a download status indicator showed progress. The final video was saved directly to their device. If they revisited a project, they could preview, re-export, or jump back into the editor, making it easy to tweak and reuse content without starting over.

Iteration 2

After deciding to launch three features, we shifted our focus to make the app feel more like the web platform, especially for returning users who were already familiar with its structure.

This version of the home screen leaned into consistency:

A structured layout similar to a web, with clear cards for each feature.

These cards opened a bottom sheet to choose between upload and record video options.

Tabs at the bottom changed to Home, Projects, and Profile.

The goal here was to reduce the learning curve and make cross-platform usage feel seamless.

Iteration 2

After deciding to launch three features, we shifted our focus to make the app feel more like the web platform, especially for returning users who were already familiar with its structure.

This version of the home screen leaned into consistency:

A structured layout similar to a web, with clear cards for each feature.

These cards opened a bottom sheet to choose between upload and record video options.

Tabs at the bottom changed to Home, Projects, and Profile.

The goal here was to reduce the learning curve and make cross-platform usage feel seamless.

Profile

The profile screen was designed to be minimal, a functional space for account and plan management. Since we had no login required for the first 5 videos, the profile mainly served as a point of access once a user subscribed or upgraded. Users could view their current plan, manage subscriptions and give feedback. We deliberately avoided crowding this screen with unnecessary settings, focusing instead on giving paying users a clear and trustworthy space to manage their account. As the app evolves, this screen is also positioned to support future features like usage history and linked accounts.

Iteration 3

At this stage, we made two major shifts:

We decided to launch only AI Captions and not all three features

We launched it as a separate, lowkey MVP under the name "Captions & Subtitles" — not under the quso brand

With this narrowed scope, the home screen needed to reflect the product’s new focus: fast, single-purpose caption generation.

For new users, the home screen was clean and minimal, keeping the focus on getting started quickly.

No tab bar, no navigation-heavy layout.

Floating "Create" button as the primary action.

User projects appear directly on the home screen, making reuse and re-exports easy.

Iteration 3

At this stage, we made two major shifts:

We decided to launch only AI Captions and not all three features

We launched it as a separate, lowkey MVP under the name "Captions & Subtitles" — not under the quso brand

With this narrowed scope, the home screen needed to reflect the product’s new focus: fast, single-purpose caption generation.

For new users, the home screen was clean and minimal, keeping the focus on getting started quickly.

No tab bar, no navigation-heavy layout.

Floating "Create" button as the primary action.

User projects appear directly on the home screen, making reuse and re-exports easy.

Paywall A/B Test

To test monetisation, we used Superwall to set up two paywall variants and ran a 50/50 A/B test across platforms. Design 1 was simple and direct — all information and both plans (monthly and yearly) were shown on a single screen, with a 3-day free trial and immediate checkout flow. Design 2 was more polished and visual, featuring a large animation, a single CTA ("Start Free Trial"), and a bottom sheet that appeared afterward with pricing options. The results were: Design 1 significantly outperformed Design 2 — with a conversion rate of 11.6% vs. 7.4% on iOS, and 1.5% vs. 1.1% on Android.

Before going with Superwall, I had also designed a custom paywall internally. While it gave us full visual control, we chose Superwall for its speed, remote config, and built-in analytics — allowing us to focus on learning rather than maintaining a custom flow.

Iteration 3

At this stage, we made two major shifts:

We decided to launch only AI Captions and not all three features

We launched it as a separate, lowkey MVP under the name "Captions & Subtitles" — not under the quso brand

With this narrowed scope, the home screen needed to reflect the product’s new focus: fast, single-purpose caption generation.

For new users, the home screen was clean and minimal, keeping the focus on getting started quickly.

No tab bar, no navigation-heavy layout.

Floating "Create" button as the primary action.

User projects appear directly on the home screen, making reuse and re-exports easy.

Iteration 3

At this stage, we made two major shifts:

We decided to launch only AI Captions and not all three features

We launched it as a separate, lowkey MVP under the name "Captions & Subtitles" — not under the quso brand

With this narrowed scope, the home screen needed to reflect the product’s new focus: fast, single-purpose caption generation.

For new users, the home screen was clean and minimal, keeping the focus on getting started quickly.

No tab bar, no navigation-heavy layout.

Floating "Create" button as the primary action.

User projects appear directly on the home screen, making reuse and re-exports easy.

Edge Cases & Alerts

Explorations That Didn’t Make the Cut

First design layered too many controls over the video. The traditional horizontal thumbnail scrubber felt unnecessary.
With a linear caption editor and short-form content, the thumbnail element didn’t provide meaningful value — it only complicated the layout.
Third design's approach appeared dynamic, but in practice, it increased cognitive load. Users now had to scan multiple areas for controls.

Iteration 3

At this stage, we made two major shifts:

We decided to launch only AI Captions and not all three features

We launched it as a separate, lowkey MVP under the name "Captions & Subtitles" — not under the quso brand

With this narrowed scope, the home screen needed to reflect the product’s new focus: fast, single-purpose caption generation.

For new users, the home screen was clean and minimal, keeping the focus on getting started quickly.

No tab bar, no navigation-heavy layout.

Floating "Create" button as the primary action.

User projects appear directly on the home screen, making reuse and re-exports easy.

Iteration 3

At this stage, we made two major shifts:

We decided to launch only AI Captions and not all three features

We launched it as a separate, lowkey MVP under the name "Captions & Subtitles" — not under the quso brand

With this narrowed scope, the home screen needed to reflect the product’s new focus: fast, single-purpose caption generation.

For new users, the home screen was clean and minimal, keeping the focus on getting started quickly.

No tab bar, no navigation-heavy layout.

Floating "Create" button as the primary action.

User projects appear directly on the home screen, making reuse and re-exports easy.

What I Learned

Launching Captions & Subtitles was a crash course in fast decision-making, scope control, and designing for speed without losing clarity. I learned that simplicity outperforms, and that shipping a focused MVP, even under a different name, can teach you more than a full-featured launch ever could.

The learnings from this launch are now informing the next phase of quso’s mobile strategy, with deeper editing, smarter defaults, and expanded AI tools. And personally, it reminded me how valuable it is to design for progress, not perfection.

At quso.ai, I worked as the sole product designer on the iOS app, driving the design process end-to-end—from ideation and user flows to high-fidelity designs and handoff.

Zero to App Store: Designing quso.ai App Experience from Scratch

Zero to App Store: Designing quso.ai App Experience from Scratch

Zero to App Store: Designing quso.ai App Experience from Scratch

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