Can the BC API be used to connect/synch directly to a iPhone App (app local database)?

Question

Hi Guys,
I'm just starting a project in collaboration with an iPhone App developer, they're building an app where a user will input survey data which is saved to a database within the app, then when the phone has a connection, the data is uploaded to a database. I want to use BC and extend the CRM to store the data captured from the app against a customer/case record, which will subsequently be displayed and modified by admin staff through a web front end. If necessary I'll use a Web App for part of this functionality.
I know the BC Web Services API can connect to an external database, but before designing a solution that requires building an external database to store the iPhone app data just so that BC can connect to it, can you tell me whether it's possible for the BC Web Services API to connect directly with an iPhone App (with integrated database)?
Totally new territory for me, so any answer to my question, or other help, tips and advice will be greatly appreciated.
Regards, Mark.

Answer 1

Many thanks for your helpful feedback TheBCMan, that's very clear. The more I've researched this, the more roadblocks appear and the more it appears BC is not going to work for this project, which is a shame as some of the other BC features are perfect for the project as a whole. However, before giving up, can I run the points below by you to validate or disprove any of my current understanding?
I understand I will need to stand up an external db/app to synch with the iPhone app to save the customer survey data, and I understand I will then be able to connect the external db/app to the BC API and pull the survey data into a extended CRM form.
However, once the data is in BC, I cannot work out a way where I could edit that CRM form data with it's assigned to a Case? That is, I understand it's possible to display/edit CRM form data assigned to a 'contact' of a customer record, but the problem here is I can only access the data to edit it when logged on as that customer. But this is data a staff member will access (customers will not be able to access it) and staff will not have access to the customers login credentials. So it's not feasible to assign the CRM data at the Contact level, agree/disagree?
If I set up one staff member as a customer (so one unique login) and save all the (potentially hundreds) of survey data CRM forms as individual 'Cases', but as I understand it, whereas this overcomes the customer logn issue, I won't be able to add a web form to a page to edit the survey data CRM form, because it's assigned to a Case, not a Contact in this scenario, agree/disagree?. (This is the approach I really hoped would work out)
And as you said, I can't use a Web App, which would overcome both of the issues above, because I can't access a Web App from the BC API. 
So, in conclusion, these appear to be no way around these roadblocks, unless you can tell me otherwise?
Thanks again for your help.
Regards, Mark.