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We live in a world where everyday conveniences often come with a recurring fee; many companies are looking for an endless payday. Ultimately, buying a modern gadget doesn't always mean you're done paying for it — instead, you may have to rent its most useful features. What started as an upsell years ago is now often a trap to keep you on the hook, and companies may even limit your hardware if you don't pay for an ongoing subscription.

Thankfully, not every subscription out there is suspect, though there are certainly a few that stand out for making their associated gadgets way less useful when you stop paying. The Oura Ring is a prime example, with its more detailed analysis gated behind a paywall. Then there's Ring and its video doorbells, which let you see who's at the door but require a subscription to replay recorded footage. Whoop's fitness bands are similarly stymied; Once your membership ends, you can no longer collect and analyze new biometric data.…