Hello,
I'm sorry for my english, i'm still learning 
So here is my doubt: My phone was stolen, and my mother's phone received the sim card change SMS with the new number. I want to know if i have to send the sms commmands for my number or for the new number? and if i send for the new number, the command will work? and the person who change the sind card, will see the sms, with my passoword?
I'm thankful since already and and waiting for response
Well to be honest DJBone isn't completly right. If you send the command to the new number while the sim is in your protected android phone he won't see the message (unless you used the wrong code but I'm not sure).
However, if the thief put the sim back in an unprotected phone and you send a command he will see the command and know your password. In the best world Avast should use a different code for sending commands and granting access to the phone. But as you can see on this forum many people already can't remember a single code or don't take the time to read the help, so making the program even more complicated is probably not the best thing to do.
What Avast could do is that if you chose to only allow commands from friends numbers (the ones you entered in AT) then the code shouldn't be necessary. I think this could be a good move because many thieves don't use the phone for themselves. They start the phone with a sim just to check if everything is working and then turn off the phone and sell it to someone else. If the thief were to receive the commands, especially the self-explanatory ones like LOST or LOCATE they could figure something is going on.
