Embedding invisible metadata in EDAMNote using iOS Evernote API

Question

I am integrating Evernote with an iOS App, my customer wants the app to able to sync some Infos being generated by the user with Evernote. There will be one Notebook for this use case and one Note will be created for each Element of the app to be stored on the cloud, to succeed with sync each note has to store some metadata that should be only interpreted by the app and not visible through the web interface or desktop/mobile clients.

I have came up to 2 possible solutions but they do not make me completely happy:

SOLUTION 1:

Create Tags to store the metadata related to one Note, for each metadata-field there will be a new Tag like "myapp_title" or "myapp_info1".

PROs: The app can download all the notes from the notebook and extract the infos stored in the Tags.

CONs: The user's account will be full of Tags that make only sense for the app, tags should be deleted if App Elements are deleted...

SOLUTION 2:

Include at the end of the Note a part to be only interpreted by the app, some kind of pre-formatted text that should only be read by the app.

PROs: No need to messup Tags

CONS: User can delete this information by mistake (or on purpose). Visible by the user...

Do you guys know a solution for this? Does the API allow this kind of "hidden" metadata?

Every help or clue would help a lot..

Thanks

Answer 1

Use the new Note.attributes.applicationData field: http://discussion.evernote.com/topic/22731-api-updated/

Answer 2

As answered on the developer forum, by SethH.

You can add metadata to the Note.attributes.sourceApplication field, which our apps don't use or expose to the user. Please insert your metadata in the form consumerkey:{metadata} and play nicely with data that other apps might stash in this field.

Is there any favored delimiter to use to separate from metadata other apps have left, or is it just left up to each developer?

Let's go with semicolon:

consumerkey:{metadata};consumerkey:{metadata}