Smart MultiCalculator – All-in-One Android Calculator App (29+ Tools, AdMob + Unity Ads)

Smart MultiCalculator – All-in-One Android Calculator App (29+ Tools, AdMob + Unity Ads)
Smart MultiCalculator – All-in-One Android Calculator App (29+ Tools, AdMob + Unity Ads)

Smart MultiCalculator – All-in-One Android Calculator App

Smart MultiCalculator is a powerful and versatile Android application built with Kotlin & Jetpack Compose. It combines 29+ calculators across multiple categories into one clean, colorful, and professional app. Perfect for students, professionals, engineers, business owners, and everyday users.

✨ Key Features:

  • 29+ calculators across categories: Basic, Scientific, Financial, Health, Engineering & Miscellaneous
  • Modern & responsive UI with gradient tiles and dynamic dashboard
  • Built using Jetpack Compose with clean architecture
  • Supports Android tablets, Fire Tablets, and Fire TV
  • Integrated AdMob (Banner, Interstitial, Rewarded, App Open Ads)
  • Integrated Unity Ads for extra monetization
  • “Go Ad Free” unlock option with rewarded ads logic
  • Lightweight, optimized performance, easy to customize

Technologies Used:

  • Kotlin – Primary language
  • Jetpack Compose – Modern UI toolkit
  • Navigation Compose – Smooth navigation between screens
  • Hilt – Dependency Injection
  • AdMob + Unity Ads SDKs

What You Get:

  • Full Android Studio project source code
  • Clean, modular, and well-documented codebase
  • Documentation (PDF) for setup, configuration, and customization
  • Ready-to-publish app with AdMob & Unity Ads integration

Categories & Calculators Included:

  • Basic & Advanced: Standard, Scientific, Programmer, Graphing, Fraction, Matrix, Equation Solver
  • Financial: Currency Converter, Loan/Mortgage, Tip, Discount, EMI, ROI, Tax
  • Health & Fitness: BMI, Calorie, Body Fat, BMR
  • Engineering & Utilities: Unit Converter, Ohm’s Law, Physics Formulas, Fuel Consumption, Date & Age
  • Miscellaneous: Percentage, Statistics, Probability, Time, Zakat/Donation, Cooking Converter

This source code is ready to be published on the Play Store or customized for your projects. It is designed with scalability and monetization in mind.

APK: https://www.mediafire.com/file/pct85s207jk8xyf/SMCDEMO.apk/file
VIDEO: https://youtu.be/QTrOg6KcEUg

Changelog: Google Play Store Families Policy Compliance Fix Version 1.0.1 – Compliance Update

Technical Changes

Ad Implementation Fixes

  • Switched Interstitial Ads: Replaced InterstitialAd with RewardedInterstitialAd to ensure ads can be closed after 5 seconds, complying with Families Policy requirements.
  • Disabled App Open Ads: Removed app open ad functionality as they cannot be made closable within the 5-second requirement.
  • Updated Ad Loading Logic: Modified AdManager.kt to use rewarded interstitial format for all navigation-triggered ads.

SDK Updates

  • AdMob SDK: Updated from 23.2.0 to 22.6.0 (compatible with minSdk 21).
  • Unity Ads SDK: Updated from 4.10.0 to 4.9.2.
  • Unity Mediation: Updated from 4.10.0.0 to 4.9.2.0.

Code Changes

  • ads/src/main/java/com/aclabs/ads/AdManager.kt
    • Changed InterstitialAd to RewardedInterstitialAd
    • Updated loading and display methods
    • Maintained ad-free functionality
  • ads/src/main/java/com/aclabs/ads/AppOpenManager.kt
    • Disabled showAdIfAvailable() method
    • Added compliance comment explaining the change
  • gradle/libs.versions.toml
    • Updated AdMob, Unity Ads, and Unity Mediation versions

Compliance Fixes

Issue 1: Unclosable Ads

  • Problem: Ads interfered with app use and could not be closed after 5 seconds.
  • Solution: All ads now use formats that allow closing after 5 seconds.
  • Impact: Users can dismiss ads without being stuck.

Issue 2: Ad Content Rating

  • Problem: Ad content was not consistent with the app’s content rating.
  • Solution: Ensured proper ad serving through certified SDK versions.
  • Impact: Ads are now filtered for family-friendly content.

Issue 3: SDK Certification

  • Problem: Required use of Families Self-Certified Ads SDKs.
  • Solution: Updated to certified SDK versions compatible with minSdk 21.
  • Impact: App now uses officially certified ad SDKs.

User Experience

  • Interstitial ads remain functional but are now closable.
  • App open ads are disabled to prevent unclosable interruptions.
  • Banner ads remain unchanged and compliant.
  • Ad-free purchase functionality is fully preserved.

️ Build System

  • Resolved DEX compatibility issues with minSdk 21.
  • All modules compile successfully.
  • Gradle build system updated for compatibility.

✅ Testing Recommendations

  1. Verify interstitial ads appear and can be closed after 5 seconds.
  2. Confirm no app open ads appear on app launch.
  3. Ensure ad-free mode still works correctly.
  4. Test on Android API 21+ devices.

Next Steps for Play Store

  1. Build release APK with these changes.
  2. Update app content rating questionnaire in Play Console.
  3. Submit the app for review.
  4. Monitor for additional policy feedback.

Date: January 17, 2026

Status: Ready for Play Store resubmission