I tested the Ultrahuman Ring Pro: Rich in features, but still a hard sell

Long battery life. Charging case comes with the smart ring, free of charge. Enough features to please the biohackers. Might be overkill for casual users. Follow ZDNET: Add us as a preferred source on Google. A few years ago, I couldn't differentiate between the Oura Ring 3 and the Ultrahuman Ring Air. Both smart rings both held a similar position in the wearables market -- industry newbies with a novel design and insights you couldn't get from smartwatches. Oura was the fan favorite, but Ultrahuman offered up a unique value proposition in its subscription-free business model without a paywall. Two years later, the latest generations of both smart rings are…