Yes, you are able to fit a smart lock onto your front door. If you speak to your installer he can show you the different options that are available.
Smart locks are designed to replace traditional key opening systems and come in a variety of different styles with a choice of opening methods, from smart phone proximity through to high-tech fingerprint readers or other biometrics. The locking system will normally require some form of power to operate, and this will be a consideration about how the system will be fitted to your home.
When specifying a smart lock for your front door, you will normally also have a back-up system in place so that if the smart system fails, you can still open the door with a regular key. this means that if you lose your phone, or there is a power failure, you will still be able to get into your home.