Making offline database application on WP7 - find the right way

I need to build an offline database application on WP7. App is simple - it's about making orders from our clients, then translate it to main server (MS SQL).

Spend a days read about existing techologies - but I'am still confused. Which is right for that project?

1. Sync Framework. Looking good, but as I understand - it provides single tables - no reference beetwen them. All the references I have to build on client side. Sad.

2. Entity FrameWork on server side. And I have no clue - what can I use on client side. Is there a way to serialize entity object to Isolate Store, then restore it, and continue work with it? May be I can use Sync FrameWork, but scheme will become strange then - kinda one way.)))

3. Working with WCF & XML - most simple for me. A lot of code and conversion, but in开发者_如何学运维 this case I understand the data flow. In other view - I already have app with pure SQL-queries. I wanna be advanced. ))))

4. Using ext. databases (siaqodb for example). Which one? siaqodb suppots "Sync provider", but it doesn't support references beetwen objects - so I have to build them by myself? Any gain? I don't know.

Is there another way to build such apps? Point it please.

If this has to be done offline, then I would generally use something like:

• storing the minimal amount of the required data within isolated using a WP7 specific database like Sterling
• using either a new REST or a new RIA/WCF service with objects/functions you define in order to provide the required data synchronisation

I think this is your option 3?

I've never really liked automatic data synchronisation. I just find it easier to code the sync and deal with the error cases myself - this is especially the case if your wp7 client app uses quite a small footprint of data in relation to the larger main server db.