More than 20 cities and towns are on the map in and around the Phoenix metropolitan area, which is considered a hot spot for potential business startups — and entrepreneurship experts says the most promising municipality in the area is Tempe. One reason cited for that conclusion is that Tempe is the home of Arizona State University’s largest campus and has become a nexus for the spinout of hundreds of startups and other business expansion ventures. The development of that trend is attributed in large part to the high numbers of new and well-skilled engineers graduating each year from the Fulton Schools, one of the largest engineering schools in the United States. (Access to the full story is available only to Bizjournals.com subscribers. Nonsubscribers can create a free account to see news content.)