The time for recounting the storage in my office!

About 1300 different products with barcodes. I want to use a mobile device
with pocket EXcel, and need the A coloumn to jump one cell to the right once
it has a value. In coloum B i want to input the number of products in stock.

Once I key in an integer there, I want the excel sheet to jump once cell down
and once cell left, in order to be in coloum A - ready for me to scan the next
barcode.

How do I set this up?

Appretiate the help