The One will almost certainly fit in your pocket, but not while it’s attached to your phone. The arrangement is more handycam-like, with the DxO One sitting sideways on the bottom of the phone. It’s also not really designed to stay on your phone all the time. While the DxO One has its own shutter button, it doesn’t have any control rings or dials.

This lets the phone act as the preview screen, and gives you a way to fiddle with manual settings like aperture and shutter speed. It features its own sensor, lens, storage and processor, but plugs into the Lightning port on your iPhone. Own an Android? You’re out of luck it only works with iOS devices. Even if it may cost more than what you spent on your phone. The DxO One is a small, palm-size camera that can be thought of as an iPhone accessory. Whether most people should consider buying one is another question, though. And at £449 there’s no huge price benefit either. However, we don’t think we’re ready to trade in our high-end compacts just yet. It’s a lot like the Sony QX100, but smaller and a bit more convenient. It has a lens and sensor, similar to what you might find in an advanced compact camera like the Sony RX100 IV, but borrows your phone’s screen so the camera itself can stay absolutely tiny.

The DxO One is a small camera that plugs into an iPhone to radically improve the quality of photos you can take while on the go.

Dxo one reviews