Employer Tracking Software

Hello, I have had Iphones for several years for my business as a photographer. In 2021, I had to return to an industry that is 100 percent remote. I worked for several different employers where I had to use my personal Iphone that I also use for my business as a photographer. I am inexperienced in technolgy and protecting myself on phones, tablets, laptops and pcs. Two of my remote employers did quickly put tracking devices on the current iphone I use that I pay for as my business account which is also linked to a tablet. How can I remove this tracking without compromising my data saved, photos, personal documents like W-2s and paystubs, and can I sue them?