You can select your login method or start a new game from the main menu:
 

Guest

  1. Launch the game
  2. Tap on Options
  3. Select Log Out
  4. When at the Title Screen, tap on Login
  5. Tap on Change
  6. Tap on Guest and Login

Google Play:

  1. Launch the game
  2. Tap on Options
  3. Select Log Out
  4. When at the Title Screen, tap on Login
  5. Tap on Change
  6. Select Google Play and Login

Game Center:

  1. Launch the game
  2. Tap on Options
  3. Select Log Out
  4. When at the Title Screen, tap on Login
  5. Tap on Change
  6. Select Game Center and Login

Sign in with Apple:

  1. Launch the game
  2. Tap on Options
  3. Select Log Out
  4. When at the Title Screen, tap on Login
  5. Tap on Change
  6. Select Apple and Sign in

Amazon:

  1. Launch the game
  2. Tap on Options
  3. Select Log Out
  4. When at the Title Screen, tap on Login
  5. Tap on Change
  6. Select Amazon and Sign in