I have a long (possibly, around 2500-3000px) mobile page which content is divided into three sections. The page has a header for global navigation. I am now wondering should I have a subheader for local navigation for these three sections.See image below.
Is this type of local navigation a good idea and if so, when it should be used (e.g., how long the page should be)? Also, if a subheader is used should both headers collapse when the page is scrolled down?
There is already a similar question about this, but it did not clearly answer my problems about page length and the overall necessity of subnavigation in mobile web pages.
Furthermore, I would appreciate if there are any good examples of local navigation on mobile web.