Depends on your living situation, but I replaced the exterior door locks with digital combination locks.
Not, repeat, not, networked in any way.
My kids have codes. My best friend has a code. The neighbor across the street who we trust has a code. Now none of them need to have a key. And best of all, I am never locked out of the house because I forgot my keys.
And should one of them prove untrustworthy, that code can be deleted.
9V battery lasts 2-3 years. If your door has the right holes already, takes 30 minutes and no special tools to install.