I have an xperia xz
I just bought it two weeks ago, so my phone is still very new. However, during my use I noticed that the phone is not responsive, when I tap on any icon, it takes between 4 to 5 second for the phone to respond. Then, the phone freezes and stucks a lot, many apps even the built one don't respond and it displays to me whether I want to close the app or wait. I turned of the stamina battery mode and I deleted most of my recent installed apps, nothing happened, I have to restart the phone several times a day. Eventually, I made a factory reset and I am using the phone. It's better now but still, the phone is not responsive, it still takes few seconds to open anything, for example, if I open the messaging app, I will have a white screen first, then the screen flicks a little and then I will have my messages. If I click the home icon afterward, I hear the click sound, but after 3 to 4 seconds and the icon home gets highlighted and 2 to 3 seconds more the the phone displays the home screen. This is really ineffective, this is not normal, I used to have an iPhone 6 plus and it's much way quicker and very responsive, you tap on any icon or app, it immediately opens, less than a second
Thanks
