Smart bulbs can be controlled when you are away, through an app on your phone. They can also be programmed to turn on when you are near your home so you arrive to a well-lit home (called geolocation). Finally, you can set up vacation settings so the bulbs turn on and off randomly to make it look like you are home.
The biggest drawback of smart bulbs is you need to use an app or voice control to operate them. If you turn off the wall switch, then you disable all the smart features of the bulb.
I recommend that people look into smart switches when possible. While they require a little more work it install, they operate like regular switches, but with the additional smart features mentioned above.