This is not possible because electromagnetic waves emitted by alarms are encoded at very low frequencies (+- 430Mhz) relative to a smartphone, it would not be possible to reproduce this type of wave through a cellular device without specific hardware to properly emit and encode this wave.
Detail: If a determined criminal really wants to get into your car, you can use a code grabber (alias Chapolin) to make a copy of your "key". A code grabber is a radio receiver sensitive to your transmitter’s signal. It receives the code and records it. If the thief intercepts your "deactivate code", you can program another transmitter to mimic exactly your unique and personal signal. With this copied key, the thief can "cheat" your alarm system the next time you leave the car alone.
To solve this problem, advanced alarm systems establish a new set of codes each time you activate the alarm. Using rotary code algorithms, the receiver encrypts the new deactivation code and sends it to the transmitter. Since the transmitter only uses the code once, any intercepted information has no value.
Unless you can figure out how to use this rotary code algorithm, it is not possible to reproduce the emitted signal.
http://carros.hsw.uol.com.br/alarmes-dos-carros.htm
About Chapolin, I recommend reading, even for those who own car with alarm!!
http://g1.globo.com/fantastico/noticia/2014/04/aparelho-que-bloqueia-travamento-de-carros-e-nova-arma-dos-bandidos.html
msantiago, you don’t want to build an app to steal a car? huaehuhua
– Marcelo Aymone
It is possible, but the problem is hardware, not programming, because the solution involves making a transmitter to add to the device (either by audio output, or usb). Maybe the best way was to solve that part, and then bring the programming problem to Sopt.
– Bacco
So, I answered that is not possible, given the conditions offered by the user, where the hardware is the S4.
– Marcelo Aymone
From the discussion and answers (after all, I don’t understand any of the subject), I agree with @Bacco that in the current formulation the problem is more hardware than software. But, still, isn’t it worth keeping the question here just to clarify this knowledge? I found potentially useful.
– Luiz Vieira
But if anyone feels like trying to continue this particular discussion, I believe it is more advantageous to open a question in the goal. :)
– Luiz Vieira
I had not voted to close when the question was asked to give time to guide the OP in the comments (and in the end came out until a reply). This already solved, I’m "pulling the queue" out of scope.
– Bacco