In November, Google Docs made is possible to edit your documents on Andriod and iOS device while on the go including iPad.
The new mobile editor is fast and lightweight, but sometimes you want to make more style edits like changing a font, or center aligning a paragraph. If you're on an iPad, you can do that by visiting the Desktop version of the document editor.
To insert formulas in a Google spreadsheet from your iPad, -- just click Go to spreadsheet view at the top of the mobile view to try out the full version. You can now insert formulas in from the editable formula bar:
Of course, mobile and even tablet browsers are still not as powerful as their desktop counterparts, which's why mobile-optimized Google documents editor for the iPad was launched.
But for one-off times when you need to make an advanced change, that Desktop link might be just what you're looking for.