Flutter

Responsibilities

• User authentication
• Video upload initiation
• Adaptive playback

Upload Flow

```mermaid sequenceDiagram participant U as User participant A as Flutter App participant API as Go API participant S3 as S3

U->>A: Select Video
A->>API: Request Upload URL
API-->>A: Pre-signed URL
A->>S3: Upload Video

```

Playback

• Uses HLS master playlist
• Player automatically switches bitrate based on network conditions