However, unless we expressly state otherwise, your right to use the Service does not include (i) publicly performing or publicly displaying the Service,

That's funny, because it seems to imply that taking a screenshot of a secret and tweeting it is forbidden (although the Secret co-founder uses them in his post explaining how it works technically.)

When you post, link or otherwise make available content to the Service, you grant us a nonexclusive, royalty-free, perpetual, irrevocable and fully sublicensable right to use, reproduce, modify, adapt, publish, translate, create derivative works from, distribute, perform and display such content throughout the world in any manner or media, on or off the App.

This got to be the most extreme copyright license in Terms of Service that I have ever seen.

Basically, it's as if you did not exist as an author. Which is fine because it's supposed to be a secret. But in the process, Secret wants all the rights for themselves (and their future business partners I assume).

(I'm not sure that most Secret messages would pass the originality threshold required for copyright and authors' right protection anyway.)

Modification to the service

Secret reserves the right in its sole discretion to review, improve, modify or discontinue, temporarily or permanently, the Service and/or any features, information, materials or content on the Service with or without notice to you.

Suspension/Termination

Secret may suspend and/or terminate your rights with respect to the Service for any reason or for no reason at all and with or without notice at Secret’s sole discretion.

Governing Law; Arbitration

PLEASE READ THE FOLLOWING PARAGRAPHS CAREFULLY BECAUSE THEY REQUIRE YOU TO ARBITRATE DISPUTES WITH SECRET AND LIMIT THE MANNER IN WHICH YOU CAN SEEK RELIEF FROM SECRET.

[…]

If settlement is not reached within 60 days after service of a written demand for mediation, any unresolved controversy or claim will be resolved by arbitration in accordance with the rules of the American Arbitration Association before a single arbitrator in San Francisco, California.

Legal Compliance

You represent and warrant that: (i) you are not located in a country that is subject to a U.S. Government embargo, or that has been designated by the U.S. Government as a “terrorist supporting” country; and (ii) you are not listed on any U.S. Government list of prohibited or restricted parties.

That's funny. I guess I don't know if I'm on a US government list of restricted parties!