eli5: What is the purpose and/or advantage of multiple cameras and lenses on a phone?

Question

As the title suggests, I don’t understand how this works.

In: 41

Answer 1

When using camera, you often want to adjust zoom and focus. This can be done by either changing the lens you are using or by moving it around in a camera.

The distance of moving the lens around is limited by how thick your phone is, and our smartphones keep getting thinner, so we get a problem. We have some software tricks to adjust zoom and focus, but those always sacrifice some image quality.

With multiple lenses we can have lenses for different zoom and/or focus and switch between them as needed. So, we can get away with much smaller window to adjust each individual lens.