Odd title but Ill try and make it make sense, currently I have a Samsung Galaxy S21 Ultra, but this has happened with previous Galaxies as well, and my ex has a IPhone

She doesnt have the password to my Verizon account as I thought that might be how originally, but she can somehow see every app I download, all my texts and pics/videos I take, even what I google and google map search, and its driving me fucking crazy

I literally have no idea what she could be using, other than possibly an old outdated phone but that doesnt even make sense, and I dont have any access to her phone at all, if any one has any suggesstions or if this isnt the right place to ask I apologize just dont know where else to turn