As of 2016, Apple's support website has a page that provides help and walkthroughs of basic functions in Numbers. Dummies.com also has dedicated pages and how-to guides for Numbers topics on iPad. YouTube videos are also available showing video examples of basic features.
The Apple support website offers Numbers help pages for both iOS and Mac platforms. The iOS page has online documentation for getting started, covering topics such as how to create spreadsheets, add tables, formulas, charts and images.
The Dummies.com website has step-by-step instructions for functions in Numbers for iPad, such as creating tables, formatting documents, using checkboxes or entering formulas.
Videos on YouTube also provide visual examples of using Numbers functions on an iPad, including templates, using tabs, entering data into cells, creating formulas and filling formulas to other cells.
The first time someone loads the mobile version of Numbers on an iPad, an image labeled Tap to Get Started with Numbers provides a spreadsheet showing basic details on how to use the app, including pinching, swiping, copying and pasting and using tabs.