I have never heard of an app that does that, but I don't have an iPhone.  But, I would recommend blocking data on your daughter's phone to prevent picture messaging.  With the inappropriate and even illegal messages that kids send each other, I would want to protect my kids from that if they were still underage.  Your daughter may never do it, but she cannot control what others might send to her.  A data block would not allow any picture messages to be sent or received.