Beacon is no longer available. The iPhone is now powerful enough to run more featureful apps very quickly. You should use one of those apps.
When Beacon was first submitted to the app store, there were virtually no apps in the "Navigation" category, so there was very little competition. Beacon rose quickly in the App Store.
Within a few months, Beacon became the #1 Free App in the Navigation category. When Apple changed the category icons to be top apps in each category, Beacon was the first Navigation category icon. Beacon appeared on the home screen in numerous Apple ads.
Beacon was hosted on the Apple Developer account of a good friend. He accidentally let his account lapse, and Beacon disappeared from the store.
I, and a mysterious man named Andreas, who randomly started sending me graphics one day, did a lot of work on a replacement app. By the time it was ready, however, the Navigation category was full of much better apps, and Beacon's continued presence in the charts had been largely due to already being in the charts.
Beacon came back to the App Store when my friend reinstated his Apple Developer account a while later. It's a useless app now, and I don't update it. It continues to collect terrible reviews.