I built a Flutter paint calculator app — here's what I learned

Boris — Wed, 25 Mar 2026 19:43:54 +0000

After releasing a tile calculator app (500+ downloads), I applied the same formula to paint calculation.
Tech stack:

Flutter + Riverpod (state management)
Hive (calculation history)
SharedPreferences (settings persistence)
Material 3, green #4CAF50
flutter_localizations for i18n

Key challenges:
Units system — storing metric/imperial per saved calculation was tricky. Each history record saves its own unitSystem so when you load it back, units don't reset to current settings.
Opening deductions — supporting both standard sizes (door 2.0×0.9m, window 1.2×1.0m) and custom sizes with separate counters for each type.
Paint brand database — auto-filling coverage when a brand is selected while still allowing manual override.
The app:
Paint Calculator: Room & Wall
https://play.google.com/store/apps/details?id=com.paintcalculator.squarefeet.wallroom
Happy to answer questions about the Flutter implementation.

How I Built “Love Calculator by Name” – A Fun Offline Flutter App in One Weekend

Boris — Thu, 26 Feb 2026 12:38:49 +0000

How I Built “Love Calculator by Name” – A Fun Offline Flutter App in One Weekend
As a Flutter developer with over 3 years of experience and 20+ apps already published on Google Play, I still love building small, joyful utility apps. They are perfect for practicing new techniques, testing animations, and shipping something fun in just a few days.
This time I decided to revive a classic — the “Love Calculator by Name”. You know, the one where you enter two names and get a funny love percentage with hearts and confetti. In 2026 it still gets thousands of downloads because people love simple, shareable entertainment apps.
In this article I’ll show you exactly how I built the complete app using only Flutter — fully offline, beautiful animations, share feature, and ready for Google Play.
Tech Stack (kept it minimal and modern)

Flutter 3.24+
Dart
Packages:
confetti – for the exploding hearts
flutter_animate – super easy animations
share_plus – one-tap sharing
google_fonts – nice romantic fonts

No Firebase, no backend — 100% offline.

The Love Calculation Logic
The heart of the app is a deterministic (but still fun) percentage calculator:

Dartint calculateLovePercentage(String name1, String name2) {
  final combined = (name1 + name2).toLowerCase();
  int sum = combined.codeUnits.fold(0, (a, b) => a + b);
  return (sum % 101); // 0-100%
}

I also added the classic FLAMES algorithm as an optional mode (Friends, Lovers, Affection, Marriage, Enemies, Siblings) because people still love it.

Beautiful Animated UI
The main screen is simple: two TextFields and a big pulsing “Calculate Love!” button.
When the user taps, I show a 3-second animation with a growing heart, then confetti explodes and the result appears with scale + fade animation.

DartAnimate(
  effects: [ScaleEffect(), FadeEffect()],
  child: Text(
    '$percentage%',
    style: GoogleFonts.dancingScript(fontSize: 120, color: Colors.pink),
  ),
)

The result screen also shows a funny message depending on the percentage (I wrote 8 different texts).

Share Feature
One of the most important parts — users love to share screenshots.

DartShare.share(
  'We got $percentage% on Love Calculator by Name! ❤️\n'
  'Try it yourself: https://play.google.com/store/apps/details?id=com.love.calculator.lovecalculator',
);

Publishing to Google Play
Since the app is very lightweight (<15 MB), the review process took only 2 hours. Tips I always use:

Make 6–8 attractive screenshots with clear captions
Write ASO-optimized title and description (I used “Love Calculator by Name”)
Add a short 15-second promo video (recorded with the app itself)
Privacy policy is just one sentence: “This app does not collect any user data.”

Lessons I Learned (again)

Even simple apps need great animations — they make the difference between “meh” and “wow”.
Offline-first wins in 2026. People hate apps that require internet for basic things.
Share button increases organic downloads dramatically.
Testing on real devices with different languages (especially Cyrillic names) is a must.

Final Result
The app is live, clean, beautiful, and already getting positive reviews.
You can try Love Calculator by Name right now
:
→ https://play.google.com/store/apps/details?id=com.love.calculator.lovecalculator
If you want the full source code, I’ll happily share the GitHub repo in the comments (just ask).
What do you think — would you build something similar as your next weekend project? Or do you have another fun utility idea? Let me know in the comments! ❤️

DEV Community: Boris

I built a Flutter paint calculator app — here's what I learned

How I Built “Love Calculator by Name” – A Fun Offline Flutter App in One Weekend