I'm not sure if this is the right place to send this post. If not, please let me know (and to the admin : please move it in the right section).
My questions are : - what are the different GRPS / GSM modules and shields that exist ? - what's the difference between them ? - is there a library to use them ? - which one is the most popular ? (thus it will be easier to find tutorial and projects)
For more informations : I want my Arduino to send me an SMS when I send an SMS request to it (with a requesting word for example) or on a regular basis (like every hour, or day, etc.). The SMS sent by the Arduino would contain values read from a GPS chip (that I need to find as well) or any other sensor (light, acceleration ... you name it). So for example : I leave this module in my car. The board is connected on the battery (it shoudn't drain too much from a car battery, right ?). One day my car is being stolen. I send an SMS to it and the repply I get is the position, speed, etc. ... But it could be something completely different : I connect a motion detector (e.g. PIR, passive infrared receiver) on my Arduino board. I leave it in front of my entrance door. When the board detect a movement, then it sends an SMS. And if it's not just me entering my house, then ... well, maybe I should worry :/
Additional comment : I've searched the forum. a solution is to use a T68 (an old phone). but I prefer a board. then I can see people using different boards but considering the cost, I'd rather ask for additional advices.
MANY THANKS !!