Mailbox finally came up and I rejected it.

My gmail is a low priority address. Thought I would try Mailbox without worrying about my 'real' email.

Got the message that "your Mailbox is ready."

Entered email and pwd.

Next screen:

Mailbox is requesting permission to:
View and manage your mail
View your email address
Manage your contacts
Know who you are on Google
Perform these operations when I'm not using the application

Too much for me. I knew they were going to store and forward my gmail on their servers. That's OK by me since this is not a critical email account. I don't want to let it have access to my contacts etc though.

Long press and delete.