I ordered this Smart Lock for our office.What I love about this lock is that you DO NOT need to download the app in order to program it. You can easily program the keycodes and the fingerprint methods using the Quick Set Up instructions on the back of the installation guide. If you do want to download the app, you'll be able to unlock the door, and set up new users/key codes/fingerprints in the app also. I opted for to program my lock without the app, so I cannot speak to how well the app functions.You'll need 4 AA batteries to operate this lock. If you do not have the batteries on hand, you can still use this as a manual deadbolt by using the 2 physical house keys provided.The instructions were written decently well, and I followed them to install this lock. There's a video in this listing that summarizes the installation if you need to see the installation and follow along.In total, I had this installed in 5 minutes despite a small setback. My small setback was that the torque blade was too long, and I could not secure the back of the lock housing because of it. I used channel-lock pliers and linesman pliers to hold, then bent off the excess torque blade at the etched groove. It snapped off cleanly when I applied a moderate amount of pressure.When programming the keycode access, your code will need to be 8-10 digits long. No sequences (12345...) and no repeating numbers (222333444). I feel like that's a pretty long code to have to enter.If you're having trouble thinking of what you want your keycode to be, you can use an old phone number as it contains 10 digits (XXX)-XXX-XXXX. Or, you can use your favorite child's (or pet's) date of birth. But, for security's sake, probably enter it in reverse order (like this 2000-03-27), etc.If you need to reset your lock, there's a super tiny pin they provide that you stick in the reset hole. If you accidentally drop and lose this pin, you can use a paperclip to press the reset button.Lastly, this lock is a bit noisy. Even with the keypad in silent mode, the lock and unlock mechanism itself registers in the 70-decibel range zone. That's about the sound of a toilet flushing, the dishwasher, washer machine, or vacuum (according to an internet search). In some ways, the fact that it is a bit noisy acts as a deterrent for teenagers trying to sneak in past curfew. There is no sneaking in with this lock. Just something to think about; see my video if you want to hear it in action. Also, even if your keypad is in silent mode, the system beeps are still audible. So while you won't hear someone entering their code in the keypad, you will hear the "successful unlock/lock" system tones.Overall, I am very pleased with this lock. I wish it were a little quieter. But I've been looking for a lock that does not require using another app - because I already have apps for everything else these days. And this lock fits the bill and operates well.