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Mateusz
Mateusz

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I Spent 3 Days Making App Store Screenshots (So I Built a Tool That Does It in 15 Minutes)

Before after image

Why I Built Lemmi Studio

Because App Store Screenshots Are the Worst Part of Launching

TL;DR: I spent 3 days designing screenshots for my last app launch. It should've taken 15 minutes. So I built Lemmi Studioโ€”an AI tool that generates App Store screenshots, marketing copy, and landing pages automatically.

Try it free โ†’


The Problem Every mobile Developer Faces ๐Ÿ˜ซ

You've just spent 3 months building your app. The code is clean. The features work. You're ready to ship.

Then you hit the wall: marketing assets.

Sound familiar?

What You Actually Need ๐Ÿ“‹

  • 10 polished App Store screenshots (1200ร—2600px, device-framed)
  • App Store copy (title, subtitle, description, keywords)
  • A landing page
  • Everything optimized for ASO

The Problem? You Can't Design ๐ŸŽจ

Or write marketing copy. Or build marketing sites.

Your "Options" ๐Ÿค”

  1. Hire a designer โ†’ $500-1,000 + wait 1-2 weeks
  2. Learn Figma yourself โ†’ 20+ hours of tutorials
  3. Use Canva โ†’ still 4-6 hours per app
  4. Ship with ugly screenshots โ†’ tank your conversion rate

Spoiler: None of these are good if you're a solo developer shipping fast.

I know because I've launched a few apps. Every single launch, this was the bottleneck.


The Solution I Wish Existed ๐Ÿ’ก

After my last launch (where I spent 3 days in Figma), I sketched out my dream tool:

The Perfect Tool Would: โœจ

  • โœ… Take my raw iPhone screenshots
  • โœ… Generate professional device-framed marketing images
  • โœ… Write all the App Store copy (optimized for ASO)
  • โœ… Build a landing page
  • โœ… Do it all in under 15 minutes
  • โœ… Cost less than one designer hour

That tool didn't exist.

So I built it ๐Ÿค“


Meet Lemmi Studio ๐Ÿš€

logo of Lemmi Studio

Your AI-powered go-live kit for app launches.

Upload screenshots โ†’ Get complete marketing assets in 15 minutes.

Here's What It Does ๐Ÿ’ช

1. AI-Generated App Store Copy ๐Ÿ“

  • Title & subtitle (optimized for 30-char limits)
  • Promotional text (170-char hook)
  • Full description (ASO-optimized)
  • Keywords
  • Screenshot captions

Real-time character counters ensure you never exceed Apple/Google limits.

2. Professional Marketing Screenshots ๐ŸŽจ

  • Device frames (iPhone, iPad)
  • Gradient backgrounds (auto-extracted from your app colors or custom)
  • Typography overlays (10+ professional fonts)
  • App Storeโ€“ready sizes (1290ร—2796 for 6.7" displays, 1242ร—2688 for 6.5")

3. Visual Canvas Editor โœจ

  • Multi-screenshot editing workspace
  • Drag-and-drop customization
  • Change backgrounds, fonts, colors
  • Upload custom graphics and logos
  • Live preview with zoom (25%-200%)
  • Auto-save

4. Landing Page Generator ๐Ÿš€

  • Complete static website (HTML/CSS/JS)
  • Hero section, features, FAQ, CTA
  • Fully responsive
  • SEO-ready with meta tags
  • One-click export as ZIP

5. Multi-Language Support ๐ŸŒ

  • Generate everything in 6+ languages
  • English, French, Spanish, German, Italian, Polish
  • All features work in every language

How It Works (The 15-Minute Process) โšก

Step 1: Upload Your Screenshots โฑ๏ธ 2 min

Drag in up to 10 raw screenshots. Lemmi automatically detects device type and validates orientation.

upload images view

Step 2: Let AI Do Its Magic โฑ๏ธ 3 min

AI analyzes your screenshots and generates:

  • โœ… All App Store copy fields
  • โœ… Device-framed marketing images with backgrounds
  • โœ… Landing page content

Step 3: Fine-Tune in Studio Editor โฑ๏ธ 5-10 min

Visual canvas editor lets you customize everything:

  • Edit text overlays
  • Change gradient backgrounds (8 directions: top-to-bottom, diagonal, radial)
  • Upload your logo
  • Adjust fonts and colors
  • Add custom graphics

edit images view

Customize everything visuallyโ€”no code required.

Step 4: Export & Ship โฑ๏ธ 1 min

Download everything as organized ZIP files:

  • ๐Ÿ“ฑ Marketing images โ†’ upload directly to App Store Connect
  • ๐ŸŒ Landing page โ†’ download ZIP package and host anywhere (Netlify, Vercel, etc.)
  • โœ… All organized and ready to use

โฑ๏ธ Total time: 15 minutes from upload to ready-to-ship.


The Tech Stack

Frontend:

  • Next.js 15 (App Router) for Landing Page
  • React
  • TypeScript
  • Shadcn styled components
  • Fabric.js for canvas editor

Backend:

  • Express.js
  • Supabase (PostgreSQL + Auth + Storage)
  • Google Gemini for content generation
  • Prisma ORM

Infrastructure:

  • Vercel, Railway for hosting
  • Stripe for billing

Why these choices:

  • Next.js: Fast iteration, great DX, built-in API routes
  • Supabase: PostgreSQL + Auth + Storage in one, generous free tier
  • Gemini-2.5-flash: Best at maintaining context across multiple copy fields, perfect multi-modal support
  • Canvas: Battle-tested JS framework for complex client-side editing

Pricing (No Surprises) ๐Ÿ’ฐ

๐Ÿ†“ Free Tier

  • 10 credits for totally free
  • 3 projects
  • All core features

Perfect for: Trying it out or launching 1 app/month

๐Ÿ’Ž Indie โ€” $9.99/month

  • 50 AI credits/month
  • 20 projects
  • Priority support

Perfect for: Solo developers shipping regularly

๐Ÿš€ Studio โ€” $29.99/month

  • 150 AI credits/month
  • 50 projects
  • Team features

Perfect for: Small teams or agencies

What's a Credit? ๐ŸŽŸ๏ธ

Think of credits like tokens:

  • 1 credit = Generate one App Store copy field
  • 1 credit = Generate one marketing image
  • 2 credits = Generate complete landing page

Pro tip: Add-on packs available (100 credits for $5, never expire)

Why This Pricing? ๐Ÿคทโ€โ™‚๏ธ

Simple: It's way cheaper than hiring a designer ($500+) but sustainable enough to keep building features you'll actually use.


Lessons Learned Building This ๐Ÿ“š

๐Ÿ’ก Lesson 1: AI Is Great at Marketing Copy (If You Prompt Right)

Early versions generated generic, buzzword-filled copy that sounded like every other app.

The breakthrough? Feeding the AI actual screenshot images + app context. Now it writes copy that describes what your app actually does.

๐ŸŽฏ Lesson 2: Developers Want Control, Not Full Automation

I initially built this as "one-click, no editing." Users hated it.

Turns out, developers want AI to do 80% of the work but keep control over the final 20%. That's why the visual canvas editor existsโ€”complete with zoom/pan, keyboard shortcuts, and undo/redo.

๐ŸŒ Lesson 3: Multi-Language Is Harder Than It Seems

Supporting 6+ languages meant solving:

  • โœ… UI translation
  • โœ… AI prompts in each language
  • โœ… Font support for special characters
  • โœ… Character limit validation per locale

Was it worth it? Absolutely. International markets are huge for mobile apps.


What's Coming Next ๐Ÿ”ฎ

Currently shipping:

  • ๐ŸŒ In-project language switching
  • ๐Ÿค– Android screenshot templates
  • ๐ŸŽจ Premium theme collections
  • ๐Ÿ‘ฅ Team collaboration features
  • ...and more based on your feedback!

Ready to Try It? ๐ŸŽฏ

I built Lemmi Studio for developers like me who can ship code but struggle with marketing.

If you've ever procrastinated on launching because you dreaded making screenshots, this is for you.

Start Free Today ๐Ÿš€

  • โœ… Free tier with 3 projects
  • โœ… No credit card required
  • โœ… Ready in 2 minutes

Try Lemmi Studio โ†’


Let's Build Together ๐Ÿค

This is sort of MVP v1. I'm shipping fast and iterating based on real feedback.

What would make this more useful for your launches?

Reach out:

- ๐Ÿฆ X: @mateusz_b9

The Bottom Line ๐ŸŽฌ

Built by developers, for developers.

Ship faster. Skip the designer. Launch today.

Try Lemmi Studio Free โ†’

Cheers!

Top comments (7)

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shemith_mohanan_6361bb8a2 profile image
shemith mohanan

This is such a relatable pain point โ€” screenshots and ASO assets always take way longer than they should. The โ€œAI does 80%, you fine-tune 20%โ€ approach is spot on, because full automation rarely gives results devs are confident to ship.

Curious: do you plan to add preset styles based on top-performing App Store designs (e.g., โ€œcalm productivityโ€, โ€œbold fitnessโ€, โ€œfinance clean UIโ€)? That could help solo devs pick a proven template faster. ๐Ÿš€

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mateusz_b9 profile image
Mateusz

Shemith - yes! You nailed it :)

The "80% automation, 20% control" approach came from my own frustration with full automation feeling... wrong.

Preset styles are already on the roadmap! There will be gallery of presents available soon.

Question: Would you want:
A) One-click full presets
B) Mix-and-match elements
C) Both?

And which app's screenshot style would you love to replicate?

Thanks for the brilliant idea - this is exactly the feedback that shapes the product! ๐Ÿ™Œ

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shemith_mohanan_6361bb8a2 profile image
shemith mohanan

Love that presets are coming!
Iโ€™d vote for C) both โ€” quick 1-click themes + mix-and-match for flexibility. Styles inspired by top apps like Notion, Calm, and Revolut would be awesome for indie devs! ๐Ÿ™Œ

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jarne profile image
Jarne

This seems like an awesome idea. I'll definitely try it out when launching my next app. Is there an option to generate similar assets for the Play Store as well? It would be awesome to also automate that site of publishing an app. Otherwise, you'd still need to create your own screenshots, texts and SEO for the Play Store.

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mateusz_b9 profile image
Mateusz

Thanks Jarne! Android/PlayStore is part of the roadmap. It will be implemented in the nearest future.

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