There are several to make your account more secure.
  1. Make sure to protect your device with a password. Choose a long and difficult password that contains both letters and numbers to help keep your account safe. On iPad and iPhone devices you can find Passcode Options in the Settings menu and select the custom alphanumeric code option. Don’t share this password with anyone!
  2. Use Touch ID on your device: https://support.apple.com/en-us/HT201371
You can learn more on how to protect your payments here:
https://support.apple.com/en-us/HT201239"