It all depends on what kind of photo processing you need. There are applications where the filter is applied. There are more severe applications to handle. Where you can align the tone, contrast, clarity, and hue. Some apps work like a background eraser. With them, you can erase the background, and at the same time, it won't affect the central element of the photo. By the way, it is for this effect that you need to choose an application that will do everything efficiently. It's just that I've come across when some elements of the main subject can be erased along with the background. It's good that I was able to find a good app now. Write down exactly how you want to process the photo.