I’m Home utilizes Wake on LAN, a feature many computer enthusiasts who’ve poked around their computer’s BIOS have seen but may not have used. Wake on LAN is a feature that, when enabled on a PC, allows the system to be powered up from a powered off state, since most computers these days never truly power all the way off (they just enter varying lower states of power consumption).
The idea behind I’m Home is that you define what computer to wake on what WiFi, and when your phone enters and connects to that WiFi network, the I’m Home app sends out a broadcast wakeup request to your computer. You can define different computers on different networks so that your home computer fires up while you’re in the driveway and your work computer is ready when you sit down.
I’m Home is free and available from Google Play.
Download: Google Play