Fravo

walk to earn screen-time

Comment

💡 Inspiration: The Morning Run That Sparked Fravo

It all started on a crisp morning run.

As my feet hit the pavement and the morning endorphins kicked in, I felt energized, focused, and alive. But as I ran, I couldn't stop thinking about a frustrating paradox that affects almost everyone in our generation: why does 30 minutes of running leave you feeling clear-headed and accomplished, while 2 hours of passive doomscrolling on social media leaves you feeling exhausted, distracted, and guilty?

Screen time and algorithmic doomscrolling are quietly stealing 4 to 6 hours from our days. Most app limiters fail because they operate on guilt, willpower, and rigid barriers that users inevitably bypass or uninstall.

During that run, the realization hit me: What if we didn't treat screen time as a forbidden vice, but as a reward earned through healthy physical activity?

If you want 30 minutes to watch YouTube or scroll Instagram, you don't fight your brain's dopamine cravings — you get up, put on your shoes, and move your body to earn it. That morning run was the birth of Fravo: Walk to Earn Screen Time.

📱 What It Does

Fravo creates a positive, self-sustaining habit loop where physical exercise directly powers your digital life:

  1. The Step-to-Time Banking Engine: Connects directly to hardware pedometer sensors and Google Health Connect. Walking or running automatically deposits screen time into your digital bank using a mathematical conversion model: $$\text{Screen Time Earned (mins)} = \left\lfloor \frac{\text{Steps Walked}}{1000} \right\rfloor \times R$$ where $R = 30\text{ minutes}$ on the Free tier and $R = 60\text{ minutes}$ on the Pro tier.
  2. Native Accessibility App Blocker: You choose the apps that consume your focus (Instagram, TikTok, YouTube, Reddit, Twitter, games). The moment your banked minutes hit zero, Fravo's native overlay temporarily pauses those apps until you take more steps.
  3. Pippy the Evolving Companion: A reactive digital mascot that mirrors your physical energy. Pippy features 4 selectable personalities:
    • 🥊 Tough Love: Direct, no-nonsense accountability.
    • 🌟 Friendly Motivator: Warm, celebratory milestones.
    • 🧘 Stoic Guide: Calm, mindfulness-centered reminders.
    • 🦥 Chill Sloth: Relaxed, low-pressure encouragement.
  4. RevenueCat Pro Subscriptions & Viral Referrals:
    • Free Tier: Block up to 3 apps, standard 1k steps = 30 min conversion.
    • Fravo Pro: Unlimited app blocking, 2x reward multiplier (1k steps = 60 min), emergency passes, and zero ad interruptions.
    • Viral Referral Engine: Users share their personal invite code to give and receive 7 days of Pro access, managed and cached through RevenueCat.
  5. Catvertising (Ad Revenue Tracking):
    • Free users can watch optional Rewarded Video Ads (Google AdMob) for emergency unblock passes.
    • Every ad impression's micro-revenue is tracked in real-time to RevenueCat via Purchases.adTracker.trackAdRevenue.
  6. Android Home Screen AppWidget:
    • A custom Kotlin widget displaying real-time banked minutes, daily steps, and streak status directly on your launcher.

🛠️ How We Built It

  • Mobile Frontend: Built using Flutter 3.x with a custom liquid glassmorphism design system, smooth spring physics, and Hive local storage.
  • Native Android & Kotlin: Custom AccessibilityService (AppBlockerAccessibilityService) and native AppWidgetProvider for reliable low-latency blocking and widgets.
  • Monetization Architecture: RevenueCat SDK (purchases_flutter) powering native paywalls, Pro entitlement caching, restore flows, and 7-day viral referral trials.
  • Catvertising Integration: Google Mobile Ads (AdMob) Rewarded Ads forwarding real-time impression events to RevenueCat's ad tracker.
  • Re-engagement Engine: OneSignal push notifications and in-app messaging journeys tailored to the user's companion personality and distraction apps.
  • Continuous Delivery: Shorebird Over-The-Air (OTA) CodePush integrated into our production release workflow for instant zero-downtime updates.

🚧 Challenges We Faced

  1. Background Sensor Reliability: Android OEM battery savers aggressively kill background pedometer services. We resolved this by building a dual-layer sync mechanism pairing continuous hardware step counters with Google Health Connect periodic validation.
  2. Eliminating Screen Flicker During Blocking: Standard overlays often flash the target app for a split second before blocking. We fine-tuned the native Kotlin window event listeners so the Fravo block screen intercepts the foreground switch with zero latency.
  3. Psychological Balance (Friction vs. Reward): Designing an app that genuinely breaks addiction without feeling like a punitive prison required several iterations. Centering the UX on earning minutes rather than restricting time turned resistance into enthusiastic motivation.

🏆 Accomplishments We're Proud Of

  • 19/19 Automated Tests Passing: Flawless test suite covering daily rollover, Catvertising data structures, native delta calculations, and widget rendering with 0 lint errors.
  • End-to-End Catvertising: Full integration between Google AdMob Rewarded Video impression events and RevenueCat AdRevenueData.
  • Shorebird Production Build: Successfully compiled and published release 1.0.2+22 for Google Play with embedded OTA CodePush.
  • Zero-Friction Judge Onboarding: Built a dedicated promo card allowing hackathon judges to unlock 7 Days of Fravo Pro instantly on-device.

📚 What We Learned

  • Positive Reinforcement Wins: People hate being told what they cannot do. But when screen time becomes a badge of honor that you physically earned with your feet, the psychology flips from shame to pride.
  • Unified LTV Visibility: Combining subscription analytics with real-time ad impression tracking through RevenueCat provides a holistic view of user value across both free and paying cohorts.

🔑 Judge Testing Credentials & Instructions

Experience all Fravo Pro features without spending real money:

  1. Install Fravo on an Android phone or emulator.
  2. Complete the quick 30-second onboarding.
  3. On the Home Dashboard, scroll down and tap the "Invite Friends / Redeem Code" card.
  4. Enter code: FRAVO-FVPH4 and tap Claim 7 Days Pro.
  5. Your account immediately unlocks Fravo Pro with 2x reward multipliers, unlimited app blocking.

Built With

  • admob
  • digital-wellbeing
  • firebase
  • flutter
  • health-fitness
  • mobile-app
  • onesignal
  • productivity
  • reinforcement-learning
  • revenuecat
  • screentime
  • sentry
  • shipaton2026
Share this project:

Updates

Submission history