A "native app" is our case refers to the new NEO ReactNative Apps. These apps can take full advantage of the device's capabilities, including secure storage for cryptographic keys.

The "part of a large application" implies that the messenger is just a feature within a broader system a whole a social network built with UNA. In this context, it's challenging to implement end-to-end encryption because the messenger is not standalone; it's tied to other functionalities that may require different data access patterns.

Now, full end-to-end encryption comes with trade-offs. Firstly, it does require native apps on both ends to securely store keys. Web apps are generally less secure for this because the browser environment is more susceptible to various attacks.

Secondly, end-to-end encryption effectively makes moderation really difficult. If you can't see the content, you can't moderate it. For a community platform, this could be a double-edged sword. On one side, you guarantee privacy; on the other, you open up possibilities for misuse without an easy way to curb it.

If your community members are more concerned about privacy and freedom of speech and less about content moderation, then end-to-end encryption could be a good fit.