some1 sugested me for sim300....but this device do many more functions & it it complicated too.....
And you think developing your own is going to somehow be easier? You need cellular connectivity, and a GSM/GPRS module like the SIM300 is what you are going to need, that is unless you have the skills to build your own cellular connectivity module...
This isn't going to be an easy task, it's not stupid complicated either when using a cellular module to do all the heavy lifting, leaving you with just building/coding a device to read the messages and click the appropriate relays... But, it's not something someone with no knowledge is going to be able to accomplish without a steep learning curve...
It's a whole lot easier to interface a DTMF module into an over the counter phone with an auto answer circuit... A simple call to that phone and a few DTMF tones later you are up and running... I can see an inexperienced person actually being able to accomplish this with a little hard work... That and the fact there is a ton of info about using DTMF to do just this...
