SDK Apps: Persistent Config

I need a way for SDK Apps to remember admin-specified settings.

For example: Let's say I build an app that shows a bunch of clocks for a bunch of cities around the world. The MajorDomo deploys the app and needs to configure it to show the 5 cities they have offices in.

Right now the only way I can really do this is a bit kludgy - I need to create a Webform with Key/Value pairs, then read that into the app as a dataset. Which of course means that any privileged user can edit the webform and change the config inside the app.

It also means that you can't configure the app from inside the app, since the app has no way to write back to a dataset.

What would be ideal is if I had a function in the domojs library that could store an instance-specific javascript variable, and read it back out on command. Simple stuff like:

var myClocks = domo.getConfig('clocks');
domo.setConfig('clocks', myClocks);

I can then build an interface to configure the app, and just save the config back directly in that instance of the app itself. That config should be carried over when the card is duplicated, but can be left blank if the app is deployed from scratch.

If I need to do user-specific config (like remembering my individual preferences) I should be able to do that with cookies or localStorage, since the app is just running in a subdomained frame, but that's no substitute for app-wide config that should only be managed by certain users.