honestly, checking the other party's mobile won't help much if he really hiding something behind my back. My other half, he used to delete all texts and call records after each time he received them. So there are no trace of records. So, 1 day I found his company claim with hp bill attached and it revealed his constant calls to a gal and it's everyday, at least 5-6 calls, sometime when we went travelling, she will even call him midnite. So having clean phone records, doesnt mean you are safe.