Guide
How to compress a video on iPhone
Use Video & Photo Compressor: Photos or Files → choose a preset → compress → save. Encoding stays on the iPhone.
1. Install Video & Photo Compressor from the App Store.
2. Open the Videos tab and tap Select Video or Choose from Photos.
3. Pick Small, Balanced, or High Quality.
4. Tap Compress Video. Wait for the result screen.
5. Save to Photos or share. Your original is not deleted.