Sign up and log in

v.1 welcome screen

v.2 signUp screen 1

v.3 signUp screen 2

v.4 blocks for swap

v.5 blocks for swap 2

v.6 sign up function

v.7 error message

v.8 prefill email password

v.9 sign in function

v.10 sign out button

v.11 reset password

v.12 set up Firebase

v.13 create database & test (final)