A lot of people also use kik as a way to keep in touch without racking up text messages. I use Kik myself and I'm not cheating. I do have some online friends that i prefer don't have my phone number and kik provides a way to keep in contact while respecting each other's IRL privacy. I wouldnt look to much into an app on the phone unless he gives your real reason to suspect that he is using it for unsavory acts.