At some point it will occur to you that keeping 30MB buffers open to display a photo thumbnail is a really bad idea, so you will introduce 6) the buffer that is going to hold a smaller photo suitable for display in the next screen, 7) the buffer that resizes the photo in the background because it is too slow to do it in the foreground. And then you will discover that you really need five different sizes, and thus begins the slow descent into madness. It’s not uncommon to hit memory limits dealing just with a single photograph in a real-world application.