And ArcEngine wont do the job for you?
I'm asking for more specific use-cases. Ie what type of application are you building. What type of data are you pulling in (tiled, dynamic, featurelayer etc... and what kind of data is in them?). Do you require editing while offline, or will it do with disabling editing? Could you live without some data while offline? Do you require just a subset of image tiles? etc etc etc. This is a huge project, so we'd like to get the 80% use-cases solved first. So in other words, if you had to choose, what feature would then be most important, which are "only" nice to haves, what could you live without etc.
I need WPF Offline capabilities as well.
We currently are using the mobile ADF in 9.3.1 for our windows application which allows for checking in and out data from a mobile service. We also have web applications using the Web ADF.
For ArcGIS 10 we would like to move toward silverlight for the web and WPF for the windows applications. Our users need to be able to work in both Online and Offline modes using the windows application. They need the ability to check-out data and go into the field/jungle edit data and then check-in that data when returning to the office.
Can I use the Silverlight/WPF API and create a cache/work offline? Or do I need to use the Mobile SDK to create a WPF application for offline use and if so, how do I port that to silverlight?