Cross Device Rich Text Formatting

We're trying to work on a feature where users can enter rich text (Bold, numbered/bulleted lists, underlines, links) for content, but this content needs to be displayed in multiple places:

• On browser based websites/apps.
• In native iOS/Android apps.

What's the best format to use for storing this data? We are considering storing the text as html, but is this adequate, or is there a better solution/option to storing this data and rendering it?

Can native iOS/Android apps display html content well in native apps amidst other native controls, or will this text have to be converted to a different format to render well?

Thanks!