If you're looking for a way to secretly grab screenshots of what's going on on your friend's phone without them knowing, then a phone monitor is the perfect solution and also you can wrote an article to screenshot on snapchat without them knowing. Phone monitors are fairly easy to use - all you need to do is set up a secure password and then wait for the right moment to take your screenshots. You can also use it to spy on conversations or track down who's been sending naughty pictures!