This falls under the “extremely useful information” category: the Hong Kong government has just released a mobile application that shows users how long waits are at six border crossings between the SAR and Shenzhen.

There was once a day when an app like this wasn’t needed. Few Mainlanders had the ability to get into Hong Kong, and the crossings were relatively stable. But as the individual visitor scheme has expanded, more and more Mainland tourists have been flooding into Hong Kong. About 35 million Mainlanders visit per year, with that expected to increase to 50 million by 2015. This has meant waits at some border crossings – hello, Shenzhen Bay? – that are two and three hours long.

The app won’t win any awards for UI design, but it tells you what you need to know. It lists the wait at each border crossing in either direction, as well as the opening hours of each crossing.

The app also has the unfortunate name of HK ImmD. You can download it for iOS and Android.

(h/t @SlackerScholar)