The caller ID can be changed without verification in the user ID setting.
Fake calls from the new caller ID
Fake messages from the new caller ID
I have faced a critical issue with this application day before yesterday as I was completely unaware of this app. Someone had changed his VOXOX caller ID to my number and given a call to my friend in midnight and talked non-sense. The next day there was an serious argument in between us. When I checked the number in my friends cell phone, I was completely surprised.
It was my number followed by a code +1(+1-98xxxxxxxx). From my number a non-sense message had also gone to my another friend (Girl) same night. Again I found my number followed by +1 instead of +91-98xxxxxxxx. As my number is saved in the contact lists of my friends, undoubtedly my name was displayed every time. Then I came to know about VOXOX. It is a serious issue. Anyone can make fake calls and messages by using any other persons caller ID.
This is clearly violating the law.