Apple has updated iPhone's photo editing interface in iOS 13, making it more intuitive and adding a few new features and tools as well. You can now fine tune filter intensity, flip photos, and adjust their perspective along the x and y axes. Flipping a photo simply gives you a mirror image while adjusting the perspective along the horizontal and vertical planes basically lets you adjust the viewing angle, similar to Instagram's perspective correction tools. Here's how to do both on iPhone:
With iOS 11, Apple adopted the High Efficiency Image Format (HEIF) as a replacement for JPEG on both iOS and macOS. The HEIF format saves a considerable amount of storage space with its .HEIC files (High Efficiency Image Container) being up to 50 percent smaller than the same image saved in JPEG format. Despite the smaller size, the HEIF format can capture 16 bit color whereas the JPEG only handles 8 bit. Clearly HEIF is preferable to JPEG right?
When it comes to privacy, the iPhone, iPad and iPod touch always ask permission for apps to access the Camera Roll. There are several levels of permission granted to apps, spanning from full read and write access to never see photos. If you're interested in checking to see which apps have access to your photos, this information can be seen in one place.