This overall score consists of: Ease of use (60%), App responsiveness (25%), Luminosity (10%), Energy (5%).

Ease of use score made up of Set up (25%), Remote access (20%), Documentation (20%) App layout and functions (25%), and Reset procedure (10%).

App responsiveness is evaluated in a same-room scenario (the router is in the same room as the bulbs), and we judge not only the responsiveness of the bulb turning on and off, but also its dimming and changing of colour.

The lumens figure we obtain is compared against the claim on the box as a percentage, and a scale is used to assign a score based on that percentage difference.

We measure each light bulb's energy efficiency, rated in lumens per watt & the amount of light put out per watt of electricity used.

Our measure of initial average brightness refers to each bulb being fresh out of the packaging. It's possible for bulbs to lose luminosity over time.

We recommend smart lights that score 77% or more.

'Tested model' means you ought to be able to find this in retailers. We check availability every time we test, which is about 6-10 times a year.

Price for individual bulbs and kits

Price for individual bulbs paid

Assumes five hours of use per day and 19 hours in standby for the bulb only (disregarding infrastructure costs such as the router) at a cost of 30 cents per kilowatt hour; based on the out-of-box colour temperature (warm) of the bulb and maximum brightness; power consumption will vary depending on the colour temperature and brightness settings that are used. 

White: Non-adjustable tone. Warm white or cool white out of the box.

Adjustable white: Light temperature can be adjusted to warm or cool white, as well as colour tones in-between.

Adjustable colour: As well as the cool/warm white spectrum, bulb could be set to multiple colours such as red, blue, green - often up to 16 million tones.

The power of the smart light LED bulb compared to that of a regular incandescent bulb.

As tested, at full brightness, on the factory default colour setting, in kilowatt-hours.

As tested, with bulb off, but connected to the Wi-Fi network, in kilowatt-hours.

Number of life hours stated on product packaging.

The hottest part of the bulb as measured with a thermal imaging camera after being on for at least one hour.

This figure indicates the coverage you can expect.

ZigBee: Smart lights connect to a bridge/hub, which in turn connects to a Wi-Fi router.

Wi-Fi, 2.4GHz: Smart lights connect directly to your Wi-Fi router and don't need a bridge/hub.

Some smart lights require a central bridge (or hub) to work, others don't. There are benefits and drawbacks to each approach but there is an initial extra cost when choosing a light that needs a bridge.

If This Then That (IFTTN) allows your smart devices to act in a group with one action prompting another. For example, if you turn on the TV, the smart display music in the next room may turn the volume down.

Scenes are used to automatically change the brightness or colour of a lamp (or multiple lamps) to a setting that represents a task or event (eg: movie, or party).

Works by using the regional setting of the device, automatically changing colour temperature to suit time of day.

Geofencing is a virtual barrier that can act as a trigger for a certain home automation action. For example, leaving your home (with your smartphone in your pocket) could trigger a network connected alarm to activate or the lights to turn off or on.

Away mode simulates light activity, making it look like someone is home.