AstroLook

An iOS app for exploring NASA's Astronomy Picture of the Day (APOD) — a free archive of space images and videos published daily since June 16, 1995.

Features

• Today — Full-bleed hero image or video for today's APOD with title, date, and astronomer's explanation
• Browse — Pick any date range and explore the archive as a thumbnail grid
• On This Day — See what NASA published 1, 5, and 10 years ago today
• Favorites — Save any APOD to your personal collection (persisted with SwiftData)
• Search — Search the NASA Image Library by keyword
• ELI5 — On-device AI rewrites the technical explanation in plain language (iOS 26+)
• Surprise Me — Shuffle button that pulls a random APOD from the full 30-year archive
• Video support — Video APODs show a YouTube thumbnail with a tap-to-watch button
• Home screen widget — Small and medium WidgetKit widgets showing today's APOD image

Screenshots

Coming soon

Requirements

• Xcode 16+
• iOS 18+ deployment target
• A free NASA API key — get one instantly at api.nasa.gov

Setup

1. Clone the repo

   git clone https://github.com/sainag7/AstroLook.git
   cd AstroLook

2. Add your API key

   cp AstroLook/AstroLook/Secrets.swift.example AstroLook/AstroLook/Secrets.swift

   Then open Secrets.swift and replace YOUR_NASA_API_KEY_HERE with your key.

3. Open the project in Xcode

   open AstroLook/AstroLook.xcodeproj

4. Select your simulator or device and press Run (⌘R)

Tech Stack

UI	SwiftUI
Architecture	MVVM with @Observable
Persistence	SwiftData
Networking	URLSession + async/await
Widgets	WidgetKit
On-device AI	Foundation Models (iOS 26)
Data	NASA APOD API + NASA Image Library API

Project Structure

AstroLook/
├── Models/
│   ├── APODItem.swift          # APOD data model
│   └── FavoriteItem.swift      # SwiftData persistence model
├── Services/
│   ├── NASAService.swift       # All NASA API calls
│   └── FoundationModelsService.swift  # On-device ELI5 AI
├── ViewModels/
│   ├── TodayViewModel.swift
│   ├── BrowseViewModel.swift
│   ├── FavoritesViewModel.swift
│   ├── OnThisDayViewModel.swift
│   └── SearchViewModel.swift
├── Views/
│   ├── TodayView.swift
│   ├── BrowseView.swift
│   ├── DetailView.swift
│   ├── FavoritesView.swift
│   ├── SearchView.swift
│   └── Components/
└── AstroLookWidget/
    └── AstroLookWidget.swift   # WidgetKit timeline provider + views

API Key Security

Secrets.swift is listed in .gitignore and is never committed. The repo only contains Secrets.swift.example as a template. Your key stays local.