The Oura Ring 4 was fully convincing when tested and made it to number 1 on our best list. At the time of testing, no other smart ring can surpass the Oura in terms of features and operation. The sensors work reliably, both when measuring body functions and when tracking sports...

A smart ring measures pulse and skin temperature, counts steps and determines sleep quality, among other things. In this respect, it is similar to a smartwatch. But it is smaller, lighter - and less conspicuous. After all, not everyone likes to wear an occasionally vibrating mini screen on their wrist, preferring a conventional wristwatch - if they wear one at all...

The Oura Ring 4 only offers the full scope with a plan. If you don't pay, you only get the daily analysis. The accurate heart rate measurement, good training recognition, detailed analysis and good sleep recording all speak in favour of paying. It would be nice to have a charging case to charge the ring without a cable.

The Oura Ring 4 offers the best balance of design, tracking and battery, making it an outstanding smart ring as a complete package.

The Oura Ring 4 can do the same as the Ring 3, but is housed in a slim titanium casing. The battery life is good and the ring can be conveniently charged on the pad - but only with a permanent power supply. The good and detailed analysis actually speaks in favour of Oura. But it is only available with a plan (5.99 euros/month)...