[mgerdts]

If the trusted web service is under law enforcement order to decrypt mail of a particular user, a version of the JavaScript code that breaks the encryption could be delivered to only that user. No third party experts will be aware of this special version so no red flags can be raised by these third parties.

In contrast if an app does not download code, the eavesdropping will require a new version of the app to hit the app store. Third party experts may review this and raise red flags.

This is the first time I felt that an app had a privacy advantage over a browser interface.