I have an app in which I render local HTML files in a UIWebView. The files, however, are sometimes large, and getting to where you want takes a long time with the default scroll
Have considered adding # tags into your html on significant boundaries?
You could actually use native UI to implement bookmarks or a ToC for easier navigation, or simply embed links to the appropriate targets right in your html.
If you 'speed up scrolling' your app is at risk of rejection for being non-standard, since it may confuse users who are used to webviews scrolling with a standard 'feel'.