Yes, I think any moderately complete CRUD-style app is going to fall down with this approach, sadly. Even if you duplicate all of the logic that the server impl

Yes, I think any moderately complete CRUD-style app is going to fall down with this approach, sadly. Even if you duplicate all of the logic that the server implements to validate data, then that doesn't guarantee there won't be some kind of invalid interaction with a related record that only got changed on the server while you were offline. Inevitably there needs to be some kind of review screen to let the user adjust their edit in the above scenario and that makes the whole user experience a little clunky. I agree with the overall point of the OP though, given how flaky a mobile connection can be, this is by far the best approach if it suits the app.