Eve HomeKit product line
With products ranging from $39 to $79, Eve makes it easy to add sensors and smart switches to your home. Air quality, temperature, humidity are just a few of the indoor and outdoor data points you can see. You can make any light "smart" with a small outlet module that also measures energy consumption.
Insteon Hub Pro
For $149.99, the hub is the brains of your connected home, making it easy to manage and add lights, switches and sensors. Insteon offers an iOS app for device control and monitoring.
ecobee 3 thermostat
Wi-Fi and HomeKit compatible, this $249.49 thermostat can be controlled with an iOS device. It monitors the home so that you're not cooling or heating when nobody's home.
Caséta Wireless starter kit
Priced at $249.95, you'll get two remotes, two dimmers, and two pedestals for lights. Add-on dimmers and remotes cost $59.95. Siri can be used for lighting controls.