how long sms stays in phone
Verizon: Keeps records of calls and cell towers used for a year; text message details are retained for up to one year, actual text message content between 3 to 5 days; Internet session information for up to a year, and Web sites visited for up to 90 days.
AT&T: Stores call records for between 5 to 7 years; cell tower records since July 2008; text message details for between 5 to 7 years; text message content is not retained; Internet session information and destinations for up to 72 hours.