Even on a mobile device, the full desktop version let's you enter the site creator. I-phone doesn't allow photo or file upload. And the WHSYWIG editor doesn't open for text editing. Only HTML Editor is available for basic font. HTML scripting can be done for link, image, embed, tables, etc. A full version PC or MAC will be needed for Text WHYSIWIG.
Even on a PC, tables, iframes, and advanced font control HTML will be needed. Switch over to HTML editor and script away.