Making multiple worksheets in a workbook with references between the two is easy.

To create a worksheet do the following:

From the toolbar on the top of the page, tap the View (looks like an eye) menu.

Tap "Worksheets..."
The worksheets page appears
Tap the Edit button.
Tap Add Sheet.
Name the sheet in the resulting dialog.
Tap OK.
Tap Done.

The sheets appear as selectors on the bottom of the display.
Now you are free to reference cells on the other sheet with the nomenclature (same as Excel): =SHEET2!A1 - to reference cell A1 on Sheet2.