AITA for taking my friend's phone and deleting the screenshot / then telling her she doesn't know anything now

&#x200B;<br><br>My friend and I have been friends for 10 years so I've known her for a long time.<br><br>She has a boyfriend and I have a boyfriend. He and my boyfriend are close friends. We used to all hang out together and sometimes we still do. <br><br>My boyfriend and I have a shared phone lockscreen wallpaper. My lockscreen wallpaper is a screenshot of a text that my boyfriend sent me early in our relationship. <br><br>I told my boyfriend that my friend had seen the screenshot and he was not pleased. He said that he wished I had never done it and that it was personal and intimate. He said he then felt obligated to do the same so he put the same picture on his phone. <br><br>I told him he didn't have too. He said no now he wishes he hadn't done it.<br><br>My friend saw the text on my phone a few days ago. I knew she saw the text on my phone because I was in the middle of a text with my boyfriend and she pulled out her phone and said, "are you going to tell him this or should I?" And I saw that it was a text to her ex. It was a very mean and aggressive text. I just took my phone back and didn't respond.<br><br>I was mad that I had accidentally shown her something personal and intimate on my phone and that I had exploited myself by doing that. <br><br>I told my boyfriend what happened and he said to drop it. <br><br>Today my friend came over and she was texting on her phone. Her phone was sitting on the table and I woke it up and put in her passcode. She didn't see me do this. When she was distracted I walked over to her phone and opened photos. I found a screenshot of my boyfriend's text to me. <br><br>I deleted it. She saw me do this then she tried to stop me. I deleted all of the screenshots of my boyfriend's texts. When I was done I said, "now you don't know anything." <br><br>She left and didn't speak to me for days then I got a call from her boyfriend yelling at me. He said that I had violated my friend and that this was a huge violation of her personal space. He said that I'm not allowed to touch her phone and that I exploited her personal information. <br><br>My boyfriend was also mad at me and he said this wasn't any of my business and that I shouldn't have touched her phone. My boyfriend said it's not my decision and that it's his choice. He said her boyfriend is right that I violated her. <br><br>AITA?