The $9 Autonomous Key vs Spark: what nine dollars buys

Disclosure: we make Spark. The Autonomous Key's figures come from Autonomous's own page, read on 23 September 2026.

The mechanism is the whole story

A timed window is forgiving by design: tap, get an hour, and the lock returns without you doing anything. That suits somebody who wants scheduled access to a feed. A session you must end is stricter: nothing reopens on a timer, so the phone stays locked until you decide to fetch the key. That suits somebody who keeps unlocking and regretting it.

When the Autonomous Key is the better buy

• Your phone is too old for Spark — anything below iOS 17 or Android 12.
• You want the cheapest possible way to try the idea, and $9 is less than a pizza.
• A timed window is what you actually want: scheduled access rather than a lockout.

When Spark is the better buy

• You want the block to hold until you act, rather than expiring on its own.
• You are in India and want the transaction, the shipping and the support to be local.
• You want a documented escape hatch and a Strict mode that removes it.