I own six smart plugs and use four of them. The other two are in a drawer because they require a separate hub, lose connection every time the wifi blinks, or solve a problem I do not actually have.

Smart plugs are the simplest smart home gadget — you plug them into a wall outlet, plug something into them, and control the power from your phone or by voice. But not all of them work well enough to be worth the $10-25 they cost.

The Two Things Smart Plugs Are Actually Good For

Lamps and seasonal lights. Automating lights to turn on at sunset and off at bedtime is the killer use case. It makes your house look occupied when you are away and saves you from walking around turning off lamps.

Hard-to-reach appliances. That fan behind the couch or the coffee maker in the corner that stays on all day because the switch is buried — a smart plug with a schedule or voice command solves this.

What smart plugs are bad at: anything with a physical switch that needs to be turned on before the smart plug can control it. A space heater with a push-button power switch will not work because the plug can only deliver power — it cannot press the button. Look for appliances with mechanical on/off switches that stay in the “on” position.

What to Buy and What to Skip

• Best for most people ($8-15 each): TP-Link Kasa or Amazon Smart Plug. No hub required, connect directly to wifi, work with Alexa and Google Assistant. The Kasa app is better but the Amazon plug is slightly cheaper in multipacks.
• Best if you have a smart home hub ($10-12 each): Sengled Zigbee plugs (need a Zigbee hub like Echo Plus or SmartThings). Faster response than wifi plugs, do not clog your wifi network if you have many of them.
• Skip: No-name wifi plugs from brands you have never heard of. They use sketchy companion apps that may or may not be collecting data. Also skip any plug that requires a proprietary hub unless you already own that brand’s ecosystem.

Start with two. One for a living room lamp, one for a bedroom lamp. After a week you will know if they fit your life. My four active ones control three lamps and a fan. The two in the drawer were for a coffee maker (mechanical switch problem) and a TV (pointless — the TV already has a remote).