ayg wrote:

"Jump to search" will work provided that the search box has actually loaded.
Since it comes near the end of the source, that may take a while on slow
connections. Possibly move the navigation bar to the top of the source for the
main page? That would probably break all kinds of things, though, rendering the
main page differently, and people would want it for portals and stuff too. The
search box definitely can't be moved to the top by itself without either moving
the entire navigation bar or breaking the current layout, and both appear
unacceptable.

So I don't see a solution short of UA sniffing, which would require a reliable
list of mobile UA strings. Googling a bit gives http://wurfl.sourceforge.net/
and http://delicon.sourceforge.net/ as starting points for that, which needs to
be done anyway to get good display on non-CSS-compliant handhelds. Once someone
writes up code that will sniff out at least common handhelds, then we can
discuss how to handle the search box for them.

(And Rob, this bug is search-specific. Bug 1882 is a more general one.)

There are third-party solutions for this.