I normally use my Ps4 controller only on the PC and only with a cable because my PC has no Bluetooth. I wanted to connect the controller to my cell phone (Samsung Galaxy A50) today. Since I unfortunately do not have a cable with which I can connect the controller to the cell phone, I wanted to try it without. It was said that I just have to turn on Bluetooth on the cell phone and press the Playstation button and Share on the controller. Unfortunately does not work.
You have to hold down the PS button and the Share button until it flashes. Don't let go straight away.