Bisness Directory

Descripción del proyecto:
I need a mobile app designed for android, apple and windows mobile, that is to be downloaded free of charge.
This app is a business directory listing from my island. Has list with Categories, each category has a list with occupations, each occupation has a list with businesses, each business has an info page. Also needs, app-info page, submit your business-form, search with 2 options occupation or business title and ad area.
We should be able to change font size, icons, template color, and content in any area. The application will contain Greek characters.
What we want is to download the data when someone install the app and then to show this data even without internet connection, so when gets back online somehow to download the new data if exists, automatically or by asking that there is new data to download and if the user wants to download them.