Depending on the type of iPhone or iPad you have, you might be able to change your Camera app’s video settings to support better picture quality or to conserve storage space when recording. But sadly, Apple makes the process more convoluted than it needs to be.
A new free jailbreak tweak called TapVideoConfig by iOS developer SpicaT simplifies the process by letting you change your iPhone’s video recording quality from directly within the stock Camera app itself.