To Sign in to ProductPlan, visit https://app.productplan.com/users/sign_in
From the Sign in page, you can either:
Type in your email and password to sign in to ProductPlan
Click the Sign in with Google button to sign in using your Google email address that is associated with your ProductPlan account (If this is your first time signing in with Google, you will be prompted to authorize ProductPlan)
You can choose to sign in with Google or with your ProductPlan account – it’s your choice.
You can change your email address at any time by signing in to your account and clicking on “Edit Profile”.