This is a difficult problem for parents because we hate making our children cry, but it seems to me that you use 'the naughty place' / timeout and that can be effective. I don't call it 'the naughty place'.
As difficult as it is when your child cries, sometimes it is your job to be firm. At two, she is trying to assert herself. This is a normal part of development and is a good sign.
Timeout: Timeout is not a punishment. It is a stop action, relax and get-over-it place. It is quiet. Some parents have to sit with their children. In my opinion, it is only effective some of the time as the child has to cooperate.
Redirection: Redirection is also not punishment. It means (more or less) changing the subject. In this example, you remove the phone, and say firmly, "No," Then you put on some music, sing or dance, or pull out a game or activity. If you get good at redirection, it is magic because the child hardly notices they don't have the 'phone'.
Working for tokens: The token system (stickers, check marks) can be as formal or as casual as you like. Every time period (you select the amount of time) she earns a token for good behaviour. The tokens 'buy' her something she likes at the end of the day. Perhaps it is a walk before bedtime, some time on the playground, painting with mum or dad, 5 minutes of TV for every token up to the amount of time you allow TV. Everytime she is naughty, you give her a firm, "No." and remove a token. She will soon understand that she wants tokens.
I also think she has arrived at the time when she must be given choices. Choices help her to feel like she has some control and also teaches her to make decisions. You offer her the red or the blue cup. "Your choice, do you want red or blue?" She selects and you say, "You chose the red cup." It isn't more than two items and you have pre-selected the choices, so that whatever she decides is fine with you. This happens all day every time it is possible. Cookie/pudding. Red/blue shirt. This/that game. Swing/slide. Use the choosing language and it will help. When it is your choice, you say, "This time it is my choice. I choose that you cannot play with my phone. It is not your toy." By the way, don't let her play with your phone some of the time if it is a problem most of the time. They are expensive and not toys!