"Mohamed bin Nayef has changed the venues of his daily tasks, procedures and itinerary of his visits and appointments, his team of bodyguards and their methods to decrease the danger to minimum levels," Mujtahid wrote in his latest tweets on Saturday.
Mujtahid is a Saudi political activist who is believed to be a member of or have a well-connected source in the royal family.
Noting that the Saudi crown prince uses helicopter flights for most of his visits to different places, he said, "Tens of armed vehicles and over 80 security forces always accompany him during his visits."
Mujtahid said that Mohamed bin Nayef rarely stays in his palaces and uses his father's palace on an island in the Red Sea behind fortified security measures and large numbers of security forces there.
He also spends a lot of time to eavesdrop the phone calls of the ruling family members, the Saudi activist revealed.
On April 29, King Salman relieved Muqrin of his duties as crown prince and appointed his nephew, Deputy Crown Prince Mohammed bin Nayef, as the new heir apparent.
It is the first time that a grandson of the founder of the country (Ibn Saud), rather than a son, has been appointed crown prince.
Mohamed bin Nayef, 55, the grandson of the founder of Saudi Arabia, was appointed as crown prince and also minister of interior.
Saudi Foreign Minister Saud al-Faisal was also replaced by Saudi Ambassador to Washington Adel al-Jubair.
The changes signaled a major shift at the top of the ruling Al Saud family away from princes chosen by the late King Abdullah, who died in January, and towards those close to the new monarch.