Android mobile app

Hi everybody, I'd like to have a mobile app for android that let users look through database (using ajax call to external webservices) and get some data. When user download (free) the app must register to use the service (username, password, email, company name, phone), after this he can start using the basic search that allow him to get some basic data. There be a functionality that allow user to subscribe full service and pay (using paypal) the early fee. Once he did he'll able to get all data when search trough the database (150 fields). Only the user and password are stored on the mobile device and all information will be gathered from the server using ajax and xml. Even the user registration process will comunicate to the ajax webservices that will store data on the db, each time the app start have to ask for auth to the main server by passing user, device id and pwd that are stored on the main server. We have all graphic stuffs but a very simple layout sould be designed. Anyone interested?