Narwal Freo X Ultra

Suction in pascal, as the maker measures it. More pascal helps on carpet, but it says little about how well the robot picks grit off a hard floor.

A brush that guides hair to the side instead of letting it wind around the shaft. It saves the cutting work in homes with long hair or pets.

How the mop is built: flat pads, two spinning discs or a roller. Discs press harder on dried-on dirt, a roller rinses itself while it works.

How far the robot lifts the mop when it drives onto a carpet. From about 10 mm a medium pile stays dry.

The pad slides out along a wall or a kickboard, so the last few centimetres are mopped as well.

The dock washes the mop for you, so you do not rinse it by hand.

The dock dries the mop afterwards, so it does not sit there wet and start to smell.

Drying is done with warm air instead of cold. It is faster and it helps against smell.

The dock mixes detergent into the water itself, from its own bottle.

The dock can be connected to the tap and the drain, so you never fill or empty a tank. It does need a connection nearby.

How the robot maps your home and follows that map. Lidar measures with a laser and works in the dark, a camera looks along and recognises more.

How the robot sees loose things on the floor, such as cables, socks or a pet accident. A camera with depth sensing sees more than a bumper that reacts on contact.

How tall the robot is. It decides whether it fits under your sofa, bed or cabinet.

The capacity of the battery. It hints at the runtime, but how much the robot draws counts just as much.