Wink, a spinoff of Quirky, has released hardware which is now available at Home Depot and Amazon. There is an iOS app to control both the Wink hub, and some of the home automation devices you may already own.
Here's how it works: There's this Wink app, that's free in the iTunes App Store, which you can use to connect to a variety of devices like Honeywell thermostats and Schlage door locks. For things that don't fall in the "Ready to go" category, there's a Wink Hub which will communicate to those devices, like Dropcams, Leviton outlets/switches, and the Rachio sprinkler controller.
Regular price for the Wink Hub is US $79.99, but through Labor Day the "intro" price is $49.99. If you buy one Wink-compatible product you get the Hub for $24.99, and if you buy two the Hub sets you back 99 cents. Looking at the products listed on Amazon, all of them are more than $50, but if you're looking to get into home automation anyway, picking up a couple of accessories which make the Hub nearly free isn't a bad way to do it. You may find some more affordable options at Home Depot too, so it may be worth a trip to check out what's available in your region.