Thanks for requesting me.
I can confirm that you are in no kind of trouble. This is what's become known as the FBI scam.
There is NO such thing as Article 161 of US criminal law. There are 51 separate bodies of criminal law in the US and none of them has that name.
Our government needs a warrant in order to access your computer files. They can't just snoop behind your back and appear on your screen like this. Nor can you be fined without due process -- the opportunity to contest charges in court.
Actually, this is more than a well-known scam. It's a fairly nasty virus that locks the phone and tells you that you're going to get arrested if you don't send several hundred dollars to an "FBI or Homeland Security Agent."
The longer you leave the virus on your machine, the more difficulty you can get into. Not with the law, of course. The law has nothing to do with this. But not only does the virus scare you into thinking you're about to be arrested for a sex offense if you don't pay up, but it plants spyware which can lead to hacking and identity theft, and the spyware is the only real problem you've got.
You can read many scam warnings about this fraud. And here's one from the FBI , which does assure people that they are not at all involved in this particular scam.
It is not illegal to visit porn sites so long as they don't feature minors. And when Federal authorities want you, they don't give you warning and provide you with the chance to erase your hard drive or skip town or offer you a chance to buy your way out of the situation for a mere $500. They just show up at your door and surprise you with a warrant and take your electronic devices with internet acccess and/or you away with them after they've finished searching your premises.
Call your phone carrier and ask them about the FBI android scam to learn how to debug it, or ask one of our computer experts on this site how to get rid of this virus, and they can walk you through it. There are solutions to get rid of it on the web, but it's hard to know what's reliable and what will just add more spyware.
Once you've been "debugged" you'll have your computer will be as good as new. Then you can change passwords and pin numbers.