Whatsapp: Ob5

He could read messages without the blue ticks ever appearing, and he could watch Status updates without his name showing up in the "Viewed" list. The Time Traveler:

: Users can change the entire interface, including themes, fonts, and icon colors. Privacy Enhancements ob5 whatsapp

The Oppo Reno5 is marketed as a "Portrait Expert," and this extends to WhatsApp. He could read messages without the blue ticks