Matching the lock type to your existing lock should make installation easier. Key turner models fit over the existing lock and key. Some mortice locks have latch and deadbolt mechanisms installed.

An older lock design with a large 'pocket' (a rectangular block) that sits inside the door. Replacing a deadbolt with a mortice lock is possible but carving out the extra pocket space is a lot of work.

We recommend smart locks with a CHOICE Expert Rating (or overall score) of 75% or more.

This overall score is made up of ease of use (50%), unlocking (30%), unlock range (10%) and app privacy and security (10%). Range testing isn't conducted for units without Bluetooth. For these, the CHOICE Expert Rating is made up of ease of use (50%), unlocking (40%) and app privacy and security (10%).

We assess manual detail and clarity, set-up, app setup and navigation, ease of access using the primary unlock method and ease of access using the backup system.

We record the speed of the primary method of entry, followed by the speed of a secondary method of entry. We also consider any issues using the app if one is available, such as poor performance or complicated navigation.

We attempt to open the lock at three distance intervals – 20, 30 and 40 metres.

This covers five points: Can the lock be set up without an app? Is an online account needed for the app? What personal details are requested for the online account? What are the online account password rules? What security is available when launching the app?

Recommended retail or typical retail price.

Mechanism used to open the lock from the inside.

Models with a dash (e.g. 35-100) can be adjusted anywhere within the specified range. Models with a comma (e.g. 35, 45) can only be set to the specified thicknesses.

Do you need to create an account to use the app?

Is Wi-Fi connectivity built into the lock? Some models offer Wi-Fi with an optional bridge either sold separately or as part of a bundle.

Automatically opens the lock when your smartphone is within a certain radius of the door. Works with Bluetooth and Wi-Fi.

Models without key fobs don't support this unlock option.

Back-up entry option. The lock mechanism will still work with a key if you lose your phone, forget the code or if the lock's smart features fail altogether. Keyless units may require a locksmith to access if a problem occurs.

Unlock the door via the internet when you're away from home or outside the Bluetooth range. Some models offer this feature if you add an optional Wi-Fi bridge, either sold separately or as part of a bundle.

Options to allow single or short-term access with a temporary code that expires after a certain number of uses or pre-set time period.

For PIN code locks, anti-peep lets you add a random selection of numbers before and after the actual code to confuse anyone that may be watching. As long as the correct code is entered somewhere in the middle, the lock will open.

Default amount of time it takes for the lock to automatically lock if left open. This can be adjusted on some models.

Number of unlock attempts before the unit enters lockdown.

Optional activation of two methods of entry required for added security - for example, a PIN and key fob or fingerprint and smartphone.

Models that don't require an internet connection store logs in the lock then transfer them to your phone via Bluetooth.

Emits an alarm and sends alerts to your phone (remote access only) if someone attempts unauthorised entry when you're not at home.

Temporarily extends the auto lock period so the door remains open longer. Useful if you're expecting a number of guests arriving within a window of time.

Can you set up the lock without having to use an app? Some models don't require an app for operation after the initial set-up.

Back-up power options if the lock batteries die.