Comment by Daily20

You can use Screen Time to prevent yourself from installing new apps. First, delete all applications aside from your banking apps. Next, go to Settings - Screen Time - Content and Privacy Restrictions - iTunes & App Store Purchases. From here, you can disable installing apps, which hides the App Store on your phone. You can also disable Safari from Screen Time. If you find yourself turning off Screen Time, have somebody else set a four digit passcode for you. You'll be left with a phone that can only text and bank.