Offline Home Manager App Development

I need a fully offline, secure, and user-friendly mobile application for Android. This app will act as a comprehensive "Home Manager" to help users manage their shopping lists, track expenses, and monitor household items efficiently. The development should be done using Kotlin, Google's preferred language for Android app development, leveraging its modern features for a robust and maintainable codebase. All user data must be stored locally on the user's device to ensure complete privacy and offline functionality.
Core Features Required:
* Offline Functionality & Local Data Storage:
* The app must function 100% offline without any internet connection.
* All user data (lists, expenses, settings, etc.) must be stored securely on the user's phone only. No cloud synchronization or external servers are required.
* Secure Login with PIN & Recovery:
* Implement a 4-digit PIN-based login system for app security.
* Include a "Forgot PIN" option that allows users to reset their PIN using security questions (e.g., "What was your first pet's name?", "What city were you born in?").
* Comprehensive Shopping List Management:
* Multiple, Customizable List Categories:
* Kitchen Shopping List: For groceries, spices, oils, etc.
* Home Regular Item List: For cleaning supplies, personal care, general household items.
* Milk Record: A dedicated section to track daily/monthly milk consumption by quantity and rate.
* User-Defined Categories: Users must be able to create their own custom shopping list categories (e.g., "Medicines," "Electronics," "Kids' Items").
* Flexible Item Entry: Users can easily add items with custom quantity (e.g., kg, pieces, liters) and rate (price).
* Item Notes: Option to add small descriptions or notes for each item (e.g., "Brand X only," "Check expiry date").
* Reusability: Ability to view, copy, or reuse previous shopping lists for convenience.
* Robust Budget Management:
* Category-wise Budget Setting: Users can set a budget for individual shopping list categories (e.g., a specific budget for "Kitchen Shopping").
* Overall Shopping Budget: Option to set an overall budget for a complete shopping trip.
* Real-time Budget Tracking: As items are added, the app should show the remaining budget and alert the user if they exceed it.
* Detailed Expense Tracking & Analysis:
* Monthly & Yearly Expense Summaries: A clear view of total spending for each month and year.
* Category-wise Expense Breakdown: Visual representation (e.g., pie charts or bar graphs) showing how much was spent in each category.
* Historical Data: Access to all past shopping trips and their associated expenses.
* PDF Export & Sharing:
* Users must be able to export any shopping list as a PDF file.
* Option to share the generated PDF via common sharing methods (WhatsApp, Email, etc.).
* In-App Advertising Integration:
* Integrate a minimal and non-intrusive AdMob (Google Ads) solution (e.g., banner ads or interstitial ads at appropriate points). The ads should not disrupt the user experience.

Deliverables:

Upon project completion, I require:
* Complete Source Code (Kotlin): Well-commented and organized source code for the entire application, written in Kotlin.
* Signed APK/AAB File: The final Android application package ready for Google Play Store submission.
* Signing Key/Keystore File: The necessary files to sign the app for future updates on Google Play Store.
* Clear Documentation: Brief documentation on how to build, run, and manage the app's code.
Ideal Candidate:
I'm looking for a developer with:
* Proven experience in building robust, offline-first Android applications using Kotlin.
* Strong understanding of local database solutions (e.g., Room Persistence Library with Kotlin coroutines).
* Expertise in designing intuitive and user-friendly UI/UX.
* Experience with AdMob integration.
* Excellent communication skills and ability to deliver on time.