I was 11, and my mom wanted me to have it because I was doing so many after school things in middle school lol. Honestly, the longer you can go without one the better because now I'm kind of addicted whoops
Personally, I think people should get phones at an age where they are doing a lot of sports/ after school activities where they need to communicate with their rides. If you have a lot of this type of stuff, it would be a very convincing argument for convincing your parents!!