Mobile software services for telecom operators

A method for performing a telecommunication service, comprising:

• obtaining, in a first message from a mobile device and by a processor, a first phone number to whitelist,
• wherein the mobile device is registered with a call screening service, and
• wherein the first message is a text message;
• storing the first phone number in a whitelist, wherein the whitelist comprises a plurality of phone numbers allowed to contact the mobile device;
• determining that the mobile device is roaming;
• activating, by the processor and in response to determining that the mobile device is roaming, the whitelist;
• receiving, after activating the whitelist, a second message for the mobile device from a second phone number;
• searching, by the processor, the whitelist for the second phone number to generate a failed search;
• and
• discarding, by the processor, the second message based on the failed search;
• wherein the first message further comprises:
• a level of granularity indicating a type of message allowed to contact the mobile device.