MetaPi – iOS

MetaPi is an iOS application built with Swift and SwiftUI that enables users to:

• Browse images on their device
• View and edit EXIF and IPTC metadata
• Crop and adjust photos
• Set or modify location data via CoreLocation integration
• Prepare and upload images to cloud storage for use in Pi3D digital picture frames

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Table of Contents

1. Tech Stack
2. Architecture
3. Project Structure
4. Features
5. Setup & Installation
6. API Keys & Configuration
7. Build & Deployment
8. Planned Enhancements

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Tech Stack

• Language: Swift
• UI Framework: SwiftUI
• Architecture: MVVM (Model-View-ViewModel)
• EXIF & IPTC Metadata Handling: ImageIO
• Maps Display Integration: MapKit
• Location Retrieval Integration: CoreLocation
• Image Cropping: Mantis

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Architecture

The app follows the MVVM architecture to ensure separation of concerns:

• Model: Data classes and metadata parsing logic
• ViewModel: Holds UI state and business logic
• View (UI): Composable functions for screens and components

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Project Structure

MetaPi/
│
├── Components/ # Reusable SwiftUI UI components
├── Fonts/ # Custom font assets
├── Models/ # Data models, including EXIF/IPTC structures
├── Styles/ # App-wide styling, colors, typography
├── Utils/ # Helper functions (file I/O, date formatting, etc.)
├── ViewModels/ # ObservableObjects for managing screen state
├── Views/ # Main SwiftUI screens
│ ├── Dialogs/ # Custom dialogs and alerts
│ ├── SubViews/ # Smaller components used within main views
│ ├── WelcomeView/ # Onboarding/welcome flow
├── Assets/ # App icons, splash screens, image assets
├── Info/ # App configuration (Info.plist)
└── MetaPiApp.swift # App entry point

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Features

• Gallery View – Lists images from the device’s photo library
• Photo Details View – Displays full image + metadata with editing options
• Crop Tool – Powered by Mantis for intuitive cropping and adjustments
• Location Picker – Uses CoreLocation for geotagging & MapKit for map display
• Metadata Editing – Edit EXIF/IPTC data fields directly in-app
• Cloud Upload Preparation – Images ready for Pi3D frame sync

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Setup & Installation

1. Clone the Repository

   git clone <repo-link>
   cd MetaPi-iOS

2. Open in Xcode

3. Install Dependencies

• Uses Swift Package Manager (SPM)
• In Xcode: File → Add Packages... → Ensure Mantis (v2.26.0) is installed

4. Run the App

• Select an emulator and click Run.

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Build and Deployment

1. Build

• Select target device/simulator in Xcode
• Press Cmd + R to run

2. TestFlight

• Archive via Product → Archive
• Upload to App Store Connect
• Add testers in TestFlight

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Planned Enhancements

• Direct Pi3D Picture Frame integration via MQTT or cloud sync.
• Frame preview simulation.