How to make a remote control application? when to start?

What is the best framework I should use to create a remote control app for Android. I want to do something like the Tony Fadel app for Android and Iphone where you remotely control your thermostat temperature at home using a smartphone app.

I was going to use socket programming but not sure if this is the best way. If it is then I will use it, but I need some feedback before I start.

If I make one Android device a server and another device, the client I still have to manually set the IP address every time I want to connect the client to the server.

I try to avoid building a web application and making a php website to act as a server. There is too much overhead to keep the server running. would rather do something like two Android phones or tablets that can send messages to each other over the Internet or a Wi-Fi router without much effort or effort.

Any ideas on this would be needed. I can't figure out how the nest thermostat (http://www.nest.com/) works, but this is the kind of functionality I'm going to copy. I wonder if they need to use a centralized server for all the remotes. If there is a way to make it equal, that would be great. thus, all I need are two Android tablets.

Other examples I can think of are VOIP like skype and google talk. I'm pretty sure they don't use a centralized server for voice calls. My needs are much simpler. no voice or video, only sending text messages from one android device to another over the internet. Every Android device will use Wi-Fi exclusively.