It is very difficult to answer you question without having details. You should be more descriptive while asking questions in forum.
Tester can not start testing until he know the exact specification/requirement similarly it is difficult to start answering until the question is loaded with the specification.
Whatever the application is, the general roles & responsibilities of any tester is same, there will be just some enhancements depending on type of your application.
Hi ragav and kapil,
we have started bank application by using mobile web based applications,the forms like Branches,ATM Centers,etc , actually i don't know how to prepare test cases for mobile web applications.
Regards,
Venu