Displaying and Storing User Data in Firebase

MIT App Inventor Help
2

Your Firebase structure needs repair, to allow multiple pets stored by unique name:

  • Pets
    • Fleabag
      • Age: 3
      • PetType: dog
      • Weight: 20
    • Tweety
      • Age: 4
      • PetType: canary
      • Weight: 0.2
    • Meowrice
      • Age: 2
      • PetType: cat
      • Weight: 10

Also, see the advice about screens: