Kwikset Kevo & Premis Smart Locks
The Kwikset Kevo Contemporary and the Kwikset Premis smart locks are two of the best options you can buy.
Kwikset Premis allows you to connect your smart lock to HomeKit. This means you can control it with the Kwikset app and also with the Apple Home app on your iPhone and Apple Watch. This also means that you can trigger specific actions when the door is unlocked. At the door you can use a passcode to unlock it or even unlock it remotely when someone is at the door.
The Kwikset Kevo and Kevo Contemporary are Touch to Open smart locks that allow you to simply touch the lock when you are in front of the door to lock and unlock it. This model doesn't support HomeKit, but it does simplify unlocking the door, and for many people it's better than using a code.
With both of these smart locks you can share access and you can create additional keycodes for a neighbor or dogwalker to use.