An underage girl (or boy) with a technological device for communication is alone! That circumstance is already a violation of your young daughter, any random male having access to exclusive communication with her, one-on-one, on her devise. That, in itself, is child molestation.
Solus cum sola non dicunt ave.
The ubiquitous personal pocket phone is a violation of the person. It is a gross invasion of privacy that all one's calls and information be exclusively attached to oneself and thus identifiable. Once a guy contacts your underage daughter alone that is always a big red flag!
Here is a huge reason we, as a society, should bring back the public phones, beginning in the home. Get rid of the private devices! Have maximum one phone per household, and, preferably, no internet service on that device, no wi-fi in the home. Collect books, and promote the public computers again (e.g. in the local library, senior center, in the schools and other public buildings.) And let everyone use the family phone!
Every hotel, every airport should have courtesy computers and public phones available to be used anonymously and free of charge.
Our technology is ever more manipulating us. I may be OK to possess some things, but things should never possess us!