Thanks Max - OK, I think I see my confusion:
During development my app is connected to the platform - so if I'm viewing it on my iPhone that version will be unavailable during updates, and if the update produces a bug than my in-development app will be effected.
But if I deploy the app with you, that version of the deployed app is not so impacted. The update only affects my so-deployed app I choose to update the app and continue deploying on your site..
Is this correct?