Apple will eventually release a new Home app, designed to control your home automation. It’s the app that will control all equipment which is adapted for HomeKit, like garage door openers and smart thermostats.
To use it, you need accessories that support HomeKit so that they can work together. To operate, you need a Home-app that will appear in iOS9. The Home-app has the icon of a house and currently has limited functionality.
With the app, you can find suitable accessories, assign accessories to use virtual rooms and use Apple TV to control everything. So it is somewhat similar to the Health-app HealthKit. Apple employees are already testing the software. Actually, the app is currently only for internal use.
If everything goes according to plan, Apple will officially announce the first accessories in June.