External application connected to Siebel - Scenarios

Hi there,

I have a requirement that consists in developing a custom mobile application access that can access to Siebel, query data, update and create new records. The first stage would be a simple proof of concept, creating just one screen (let's say accoounts, for instance) and trying to enable basic functionalities . I have been analysing the different scenarios and possibilities and I am raising this question to the community because maybe you have been engaged in similar challenges and could give useful feedback about this.

These are the different options that I think that could fit:

1. Siebel Java Data Bean