So you want to water your garden from anywhere? The Hozelock Cloud Control Kit can help. It lets you use an iOS or Android device to create custom water schedules for your garden. You get a hub that connects to the Internet and pairs with the remote tap unit up to 50 meters away. The hub can be used to control 4 hubs at the same time.
Hozelock lets you control your garden watering system from anywhere. The companion app sends you push notifications when conditions change. More information is available here.