My wife and I both have International Phones that operate on the GSM system here with Claro. They operate, and that is about all. My wife's Motorola phone is plagued with constant pop-up text messages from Claro offering who-knows-what for 25-50 pesos. Usually pop-up when she trying to take a photo or otherwise use the phone for a phone call. My Samsung S-5 is not as prone to this, but still get occasional advertising messages that usually interrupt at inopportune times. Next season, we're getting Orange.