I discovered Teamviewer 6 the other day, and I was quite impressed. If you familiar with Hamachi, this is very similar. It allows you to remote desktop to a computer with the application installed on it, and give support/assistance or help out a friend, or whatever you choose.
You can remote from your Android device to your Windows/Ubuntu system or whatever the combination is. There is a quick sign in option, then after that, you generate a code which you use to give to the remote party, and they then connect to that device. The best part is there is no port forwarding needed. Check it out here.