Take a look at libPhoneNumber (bundled in ICS) which can help validating a phone number (see PhoneNumberUtils).
There's a MobileType you can get after validation but as stated in the source and by Ben, in some region this will not work.
EDIT:
Some validation code (here we need to check the phone is a valid one assuming it's a french one):
boolean isValid = false;
PhoneNumber number = null;
try {
number = this.phoneUtil.parse(phone, "FR"); // phone is number in internationnal format "+xxxxxx"
isValid = this.phoneUtil.isValidNumber(number);
} catch (final NumberParseException e) {
// ...
}
isValid // is the phone number valid according to the library?
this.phoneUtil.getRegionCodeForNumber(number); // this gets the country code of the phone as found by the library (for example "US", "CH", "GB", ...)
This works for us but you'll need to try it to see if it suit your need.