Disable zooming in a UIWebView _without_ setting scalesPageToFit to NO.

gistfile1.m

- (void)hijackWebViewScrollViewDelegate:(UIWebView *)webView {
  UIScrollView *scrollView = (UIScrollView *)[webView.subviews objectAtIndex:0];
  scrollView.delegate = self;
}

- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView {
  return nil;
}

// The rest of the UIScrollViewDelegate methods are not interesting for us, so forward them to the webview.

#import <objc/runtime.h>

- (BOOL)respondsToSelector:(SEL)sel
{
  if ([super respondsToSelector:sel]) {
    return YES;
  } else {
    struct objc_method_description desc = protocol_getMethodDescription(@protocol(UIScrollViewDelegate), sel, NO, YES);
    if (desc.name != NULL) {
      return [[UIWebView class] instancesRespondToSelector:sel];
    }
  }
  return NO;
}

- (void)forwardInvocation:(NSInvocation *)invocation
{
  SEL sel = invocation.selector;
  struct objc_method_description desc = protocol_getMethodDescription(@protocol(UIScrollViewDelegate), sel, NO, YES);
  if (desc.name != NULL) {
    UIScrollView *scrollView = nil;
    [invocation getArgument:&scrollView atIndex:2];
    UIView *webView = scrollView.superview;
    if ([webView respondsToSelector:sel]) {
      [invocation invokeWithTarget:webView];
      return;
    }
  }
  [super forwardInvocation:invocation];
}