Tutorials i should check to make this tiny app

hi all !!

i need to make an app for my store, i have some main categories and some products under each of them .. i need to show the prices for each product and some of them can be update everyday !! the main problem for me is (how prices can be change from time to time and users gets new price update without update whole app, any ideas / technique !!
my english is bad so i made a wireframes for my app's idea and things i need to know how to do !!



store your data in a server database, for example in a fusiontable

then after picking a product execute a SELECT statement to get the current information from the database and display it in your app

see also the tutorial Pizza Party with Fusion Tables for App Inventor 2

first do the tutorials http://appinventor.mit.edu/explore/ai2/tutorials.htmlto learn the basics of App Inventor, then try something and follow the

 Top 5 Tips: How to learn  App Inventor