Why do videos take up so much space?
Which setting to change first
Frame rate, then resolution. 60 fps only helps for fast motion and slow-motion playback; for talking, scenery or documentation, 30 fps looks the same and halves the file. Dropping 4K to 1080p is the next biggest saving and is almost always invisible on anything but a large TV.
HEVC versus H.264
HEVC (also called H.265) produces roughly half the file size at the same visual quality. The trade-off is compatibility: some older devices, TVs and web platforms cannot play it, and will either refuse the file or re-encode it — which loses quality again.
The practical rule: HEVC for storage on your own devices, H.264 for anything you send to someone else.
Why trimming a video does not always shrink it
Some editors keep the original file and store only the trim points, so nothing is actually removed until you export a new copy. If you trimmed a clip and the storage did not change, that is why — export it and delete the original.
Our iOS app for exactly this. Runs on your device — no account, no tracking.