How do you handle file uploads from mobile apps?

Files (photos, videos, documents) are uploaded directly from the mobile client to S3 through presigned URLs issued by the Laravel backend. This avoids the backend acting as a bandwidth bottleneck for large uploads. The Laravel backend handles validation (file size, MIME type, virus scanning where required), records metadata in the database, and triggers async processing (image resizing through Lambda or ImageKit, video transcoding through AWS MediaConvert) when needed. CloudFront delivers files back to mobile clients with proper caching.