Wake on LAN should work without a problem over your local network,
For wake on WAN, the Android version of Gizmo sends a wake request to the server each time it tries to connect.
The bad news is that it is tricky to set up: you have to set up wake requests to pass through your router's firmware and firewall and go directly to port 9 on you server computer.
The setup varies according to your router and firmware.
I had to configure my router to allow port forwarding to the broadcast ip address. In order to even access a broadcast ip address with my router I had to change the network's subnet mask to 255.255.255.128, which allowed me port forwarding on the broadcast ip address of 192.168.0.127; then I needed to have a wired Ethernet connection to the server. Oh, you also have to tweak the windows settings a bit to allow wake requests.
This thread from MC16 may help:
http://yabb.jriver.com/interact/index.php?topic=63581.msg425079#msg425079I remember a lot of google searches for wake on WAN helped as well. This link was also helpful for figuring out the broadcast ip address stuff:
http://www.subnet-calculator.com/The good news is, once you figure how to configure your hardware/firmware, it just works! I've been sending wake requests now for two years from Gizmo with no problems.