Mobile AI Background Changer App

I want to release a professional-looking photo editor for iOS and Android that focuses on one killer feature: swapping backgrounds with AI precision. Think real-time subject segmentation, crisp edges, and one-tap replacement with either solid colours, gradients, or custom images the user selects from their gallery.

The interface must feel polished and business-grade—clean lines, subtle animations, dark/light theme toggle—so designers, influencers, and everyday users alike sense quality from the first screen. While I’m happy for you to choose the stack that best suits the task (Swift/Kotlin, Flutter, React Native, etc.), the core image-processing model should run on-device for speed and privacy. TensorFlow Lite, Core ML, ONNX, or a similarly lightweight framework is fine as long as the final APK/IPA stays lean and the results remain sharp at up to 4K resolution.

Key expectations
• Seamless import from camera roll, live camera view, or drag-and-drop share sheet
• Automatic background removal with editable mask overlay
• Library of preset backgrounds plus user uploads
• Undo/redo, zoom, pan, and export at original resolution
• Smooth performance on mid-range devices running the current-1 OS versions

Deliverables
1. Trained model files and documented training pipeline
2. Complete, build-ready iOS and Android source code with README for local compilation
3. Figma (or similar) UI hand-off reflecting the final professional & sleek look
4. Test flight / beta release builds and a short video demo showing the feature flow
5. Post-launch bug-fix support window (timeline negotiable)

Acceptance will be based on side-by-side comparisons with industry benchmarks, average processing time per 12 MP photo (