There are two indispensable tools for tourists on the island, the St. John Map and the St. John Guidebook.
Both are published by Arne and Barbara Jakobsen and their company, Great Dane Inc.
The Internet version looks just like the one published on paper, four colors, cute cartoons and a bit of information about the island and its history.
Clicks on the pages take you to advertiser's pages with more information. It's just the thing for getting a head start on a vacation, even while you're still on the mainland.
A mobile-friendly version is also said to be available, but the Inquiring Iguana's iPhone found nothing when he clicked on the Web link via Google. Nothing but this blank screen >>>>>>>>>>>>>>>>>>>>>>>>.
A phone version would be ever so useful, with live maps and easy telephone calling. There may be a version for Android phones, but the Iguana doesn't have one of them.
In the meantime, use the old fashioned Internet site: http://www.stjohnguidebook.com/st-john-guidebook/index.html. It's very helpful.