The "Facebook Private Profile Viewer by iStaunch" is a clickbait scam. It exploits the curiosity of users to generate revenue through fraudulent verification steps. There is no technical mechanism for a third-party website to bypass Facebook's privacy settings.
Users are often forced through a series of "human verification" steps that lead to malicious downloads. facebook private profile viewer by istaunch upd
: This remains the only direct, authorized way to gain full access to a user's private posts and photos. The "Facebook Private Profile Viewer by iStaunch" is