Send automatically an SMS if SIM changed

Well, MoSync can send SMS (maSendTextSMS), but detecting sim change is trickier. You would want to save the IMEI number... Unfortunately, MoSync doesn't properly support reading that yet. See this thread.

The IMEI describes just Mobile Equipment (ME) and not the SIM.
The mobile number itself may be a point to start, but I do not know if the MoSync has possibilities to know the phone's number.

btw - knowing IMEI number is very essential in many client-server applications and would be great future to add in MoSync, I believe that you guys trying hard to add this functionality. Unfortunately IMEI is buried very deep in phone's firmware and obvious not all manufacturers wants to supply it via API.
If the MoSync core can access the phone as a regular modem, then IMEI number may be easily recoverable via AT commands.

Sorry, I got mixed up there. The IMSI, then?

AFAIK, normally, no cellphone actually knows its own number.

Also, though it varies, the IMSI is often buried even deeper.

Actually, cellphone can know its own number: Take a look at Symbian implementation: http://wiki.forum.nokia.com/index.php/How_to_get_my_own_phone_number. Do you think whether the Mosync is able to support it or not?

For getting IMEI by usinig Mosync API, I am also interested it. This is a only way to identify the phone. I just want to know what the status of implementation on getting IMEI and own phone number is.

Thanks!

I don't think we're going to be able to get the own phone number. However, we are working on reading the IMSI number, which should serve you equally well. See issues 466 and 742.