A class I sometimes use in my SASS/SCSS projects to add native-style scrolling to a fixed container in mobile or hybrid-mobile web apps.

scrollable.scss

// Native scrolling (iOS 5+, Android 4+)
.scrollable {
  overflow: auto; // Fallback for non-touch browsers
  -webkit-overflow-scrolling: touch; // Native-esque scrolling on touch-enabled webkit

  // Everything below here improves performance of scrolling. You can omit this at
  // first and add as your content becomes more complex and performance needs a boost.

  &, > * {
    -webkit-backface-visibility: hidden;
  }

  > * {
    position: relative;
    @include translate3d(0,0,0);
  }
}