Cooking Recipes Mobile App Development
Recipe app — deceptively simple task. List of recipes, detail screen, shopping list. But user opens app in kitchen, hands in flour, phone at arm's length — screen goes dark at 30-second video instruction. Let's start here.
Keep Screen Awake in Cooking Mode
When user on recipe screen switches to "cooking mode," screen shouldn't dim. iOS: UIApplication.shared.isIdleTimerDisabled = true on screen enter, false on exit. Android: window.addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON) in ViewModel via DisposableEffect in Compose or in Fragment. Without this — most common complaint in reviews.
Recipe Data Structure
Recipe — not just text. Ingredients should scale to portion count, steps — contain timers, images and embedded video of techniques.
Ingredient model: quantity: Fraction, unit: MeasurementUnit, name: String, optional: Bool. Fraction type important — "1 and 1/2 cups" multiplied by 3 should give "4 and 1/2," not "4.5 cups." Implement as numerator/denominator with simplification via GCD.
Measurement units: support conversion cups/tablespoons/teaspoons → ml → g (via Measurement<UnitVolume> on iOS, UnitConverter on Android). User chooses system (metric/imperial) in settings — all recipes recalculate automatically.
Search and Filtering
Search by name — minimum. Useful search: by ingredients ("what to cook from chicken and lemon"), by tags (vegetarian, gluten-free), by cooking time.
On iOS — CoreData with NSPredicate for complex queries. Full-text search via SQLite FTS5 if recipes > 500. On Android — Room with @Query and FTS4/FTS5 table (@Fts4 entity). Flutter: sqflite + FTS or isar with built-in search.
Filters combine (AND): time ≤ 30 min + vegetarian + in stock. "In stock" — user indicates fridge contents; app searches recipes where all ingredients marked available.
Step Instructions and Built-in Timers
Each recipe step can contain timer: "boil 8 minutes." Parse numbers and time units from step text on import. Tap timer — launch UNUserNotificationCenter notification after N seconds + local countdown.
Multiple timers simultaneously: user cooks three dishes. Store active timers in UserDefaults/SharedPreferences with exact end time — on restoration from background recalculate remaining time.
Shopping List
Add ingredients from recipe — one tap. Merge duplicates: "200g flour" from recipe 1 + "150g flour" from recipe 2 = "350g flour." Aggregation by units with conversion.
Group by categories (dairy, vegetables, meat) — manual or automatic via simple dictionary. Sync between devices: iCloud NSUbiquitousKeyValueStore (iOS) or Firebase Realtime Database.
Timeline
App with catalog, search, step mode, timers and shopping list — 3-5 weeks. With user recipes, social features and sync — 6-8 weeks.