I have a aduino uno and a gsm arduino shield. I want to send sms with different gsm networks. Each at once.
As an example if I sent "1" to arduino, it should send a sms to my mobile with the network "AT&T" and if I sent "2", a sms should come to my mobile with the network "Mobistar".
There's only one sim slot in the gsm shield. How can I achive this?