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Pros & Cons
Pros
- + Retrofit design keeps existing deadbolt and keys
- + Built-in WiFi eliminates need for separate bridge
- + DoorSense detects if door is open or closed
- + Works with Alexa, Google, and Apple HomeKit
- + Auto-lock and auto-unlock based on phone proximity
Cons
- – WiFi drains batteries faster (3-4 months reported)
- – Auto-unlock via geofencing is inconsistent
- – App can be slow to respond
- – Calibration process frustrates some users
Best Price for August Wi-Fi Smart Lock (4th Gen)
$229.99
Check Price on Amazon →Affiliate link — see disclosure
What Real Users Say
R u/apartment_renter on r/smarthome"The retrofit design is perfect for renters. Keep your landlord's deadbolt and just add the August on top. Easy to remove when you move."
R u/homekit_user on r/homeautomation"Auto-unlock works about 70% of the time. When it works, it's magic. When it doesn't, you're fumbling for your phone."
A TechReviewer42 on Amazon"Battery life with WiFi enabled is only about 3 months. Wish they'd gone with a rechargeable option."
The August Wi-Fi Smart Lock (4th Gen) earns a 76/100 community sentiment score. Its retrofit design makes it the go-to pick for renters and anyone who wants smart lock features without replacing their existing deadbolt. The trade-off? WiFi-related battery drain and inconsistent auto-unlock.
The Retrofit Advantage
August’s core appeal is simple: you keep your existing keys and deadbolt. The lock installs on the interior side of your door in about 10 minutes. For renters, this is a game-changer — you get smart lock functionality without any permanent modifications.
The DoorSense feature adds a magnetic sensor that detects whether your door is actually closed and locked, not just whether the deadbolt is thrown. This distinction matters for security notifications.
WiFi: Convenience at a Cost
The 4th Gen’s built-in WiFi means you don’t need the separate August Connect bridge that previous models required. Remote lock/unlock, status checks, and guest access all work without additional hardware.
The downside is battery life. Community reports consistently cite 3-4 months with WiFi active, compared to 6+ months on Bluetooth-only mode. The lock uses 2x CR123A batteries, which aren’t cheap.
Auto-Unlock: Hit or Miss
The most divisive feature in community discussions. Auto-unlock uses your phone’s GPS to detect when you arrive home and unlock the door automatically. When it works, it feels like the future. When it doesn’t, you’re standing at your door waiting.
Community consensus puts reliability around 70-80%, varying by phone model and GPS accuracy. Most users report it improves after the first week as the geofence calibrates.
Platform Support
Apple HomeKit: Full support including Home Key on supported devices.
Google Home: Lock, unlock, and status checks via voice.
Alexa: Full control including routines integration.
Home Assistant: Works via HomeKit controller or the August cloud integration.
Where to Buy
Bottom Line
The August Wi-Fi Smart Lock earns its 76/100 score as the best retrofit smart lock available. If you can’t or don’t want to replace your deadbolt, this is the one to get. Just budget for battery replacements every 3-4 months and temper your expectations for auto-unlock.
Sentiment data sourced from r/homeassistant, r/homeautomation, r/smarthome, and Amazon verified reviews. Last analyzed: March 2026.