Don't try to be a good dad and tell your daughter not to use the App. At least on your Tablet as you are not happy with her using the app. Even if she gets angry, tell her to deal with your decision. Apps like Kik are not good for young kids especially the daughter. It is a social messaging app but people use it to share explicit images and also as the portal for dating.
If you have a computer, check if she has installed the app on her computer. as many websites provide the tutorial to install such apps on the computer even if the user does not have access to the smartphone or tablet.