The Internet of Things has made it easier than ever to set up a smart home in which you can remotely control your door locks, lights, thermostats, vacuums, lawn mowers, and even pet feeders, using your smartphone and an app. It's also made it simple (and relatively affordable) to monitor your home from pretty much anywhere. Smart security systems are highly customizable and available as do-it-yourself kits or as full-blown setups that include professional installation and monitoring.
Depending on your needs you can go with a system that you monitor yourself, or pay a subscription fee to have your home surveilled 24/7 by professionals who will contact your local fire and police departments when alarms are triggered. You can even take advantage of on-demand monitoring services for when you're away on vacation. Of course, the more coverage you have, the more you can expect to pay.
If you're not ready for a dedicated security system, there are plenty of individual devices available that let you monitor your home from anywhere using your phone or tablet, including indoor and outdoor security cameras, video doorbells, motion sensors, and smart locks.