Compared to iOS (iPad, iPhone, iPod Touch), Android does things differently. The first tap immediately follows the link, even on menu items with dropdowns. To open a dropdown, it requires a swipe that starts on the menu item and ends off of it. This is best approximated by a downward swipe.
Force Click Trigger on Android
As of UberMenu 2.4, the first click on an Android device will open a submenu (if present), and the second click will follow the link, similar to iOS.
UberMenu 2.3 and earlier
UberMenu implements a “Force Click Trigger on Android” option that makes Android behave more like iOS, which can be enabled or disabled in the control panel. The drawback is that to follow a top-level menu link, you need to hold, then choose “open link”, rather than just tapping.