The Good: From its improved design and easy install, to its simple software interface and top-notch performance, the $229 second-generation August Smart Lock does everything a little bit better. Oh, and it integrates with Siri via Apple's HomeKit software, as well as the Works with Nest platform. The Bad: The lock isn't compatible with every deadbolt, HomeKit can be challenging to get up and running, and the Siri integration won't matter to August's non-Apple users. The Bottom Line: August's HomeKit-enabled Smart Lock 2.0 improves on an already awesome product and is worth strong consideration -- even if you don't have an iPhone. Startup August announced back in October 2015 that a second-generation Smart Lock would be heading our way soon. Fast forward to, well, right now and the August Smart Lock 2.0 is finally here for $229 on August's site, Amazon and Best Buy. While this is technically a US-only product because it's "optimized to work in North America," Amazon will ship the Smart Lock internationally -- the price coverts to roughly \u00a3150 and AU$315 at the current exchange rate.Smart locks are a fickle category. Because they're securing your front door, you want something durable and reliable that will actually make your life easier. But that hasn't always been our experience during testing. Some models are hard to install, others have confusing apps or hit-or-miss performance. The next-gen August Smart Lock has none of that nonsense. It looks good, it's reliable, the app is easy to use and this version works with Nest, Logitech Harmony, Comcast's Xfinity Home and Siri. So even if you aren't an iPhone user, I'd still strongly recommend August's Editors' Choice award-winning HomeKit-enabled Smart Lock.Leave the deadbolt, take the smart lockLike August's original Smart Lock, which is available for the reduced price of $199 while supplies last, version 2.0 retrofits to existing deadbolts. Be sure to check out the full list of compatible deadbolts before you buy, but it will typically work with most thumb-latch models from Baldwin, Kwikset, Schlage and other widely available brands.Overall, the Smart Lock's aesthetic doesn't deviate much from the original model. It's available in either a silver or a dark gray finish, with both copper and red finishes planned for future release. And, at 3.39 inches tall by 3.39 inches wide, with a depth of 2.22 inches (8.6cm round by 5.6cm deep), it's larger than a standard doorknob, but unobtrusive nonetheless.You won't notice any major design updates, but August did smarten up its configuration to make the physical hardware easier to interact with. A new easy-grip pattern and rounded edges improve the ergonomics of manually locking and unlocking the Smart Lock. The team also added magnets and a tweaked design to better secure the faceplate which hides the four included AA batteries. The plate on the original model tended to slip off when you turned the lock. (Battery life will vary a lot depending on usage, but August says it should last about 6 to 9 months.)Beyond ease of use, the Smart Lock also looks slick and feels durable -- especially compared to a similar design like the Poly-Control Danalock. It's a little tougher to compare style when you venture over to models like the Schlage Sense Bluetooth Deadbolt, which require a full replacement of your existing deadbolt. Even so, the second-gen August Smart Lock holds its own as a clean-looking piece of hardware on your front door.August's design is also discrete since you install it on the inside of your door. Since you keep your old deadbolt in place, your original keyhole and house keys will still work the same way. And everything will look exactly the same from the exterior of your house -- a plus if you want a smart lock, but don't want people to know you have a smart lock.Installation in five easy stepsIt's extremely easy to install the August Smart Lock. If you're someone who's interested in do-it-yourself smart home projects, but is new to DIY in general, this would be a great place to start. Assuming your deadbolt is compatible, you should only need a screwdriver (I needed a Phillips-head, but I supposed this could vary depending on your deadbolt) and about 10 to 15 spare minutes to swap out your old lock.Here are the steps: \t \t1. Make sure your deadbolt is compatible. Again, check this compatibility chart to make sure your hardware will play well with August. \t \t2. Remove the thumb-latch on your old lock. Use a screwdriver to remove the screws on your existing thumb-latch; remove the thumb-latch.3. Attach the August mounting plate to your deadbolt. Line up the mounting plate August provides with the tail piece of your deadbolt (that's the bit of hardware sticking out that rotates your deadbolt open and closed) and use the screws from your old lock to secure the mounting plate to the door. \t \t4. Attach the adapter to the back of the lock and lift the wing latches. Select the adapter that's compatible with your tail piece, attach it to the back of the lock and lift up the wing latches on the lock. (August provides three adapters; I used the green one because it works with my Kwikset deadbolt, but you can figure out which adapter is best for your deadbolt in August's detailed installation guide.) \t \t5. Connect the lock to the mounting plate and flip down the wing latches. Fit the lock over the mounting plate on your door (you'll feel it snap into place) and close the wing latches to secure it in place.That's it, you're done. Again, it feels a little unfair to compare this setup to models that require a full deadbolt replacement. Even so, this lock is by far the easiest to install out of all the models we've reviewed so far.