Cell phone conversations are usually frowned upon in museums and galleries and cultural attractions. But this device is becoming a welcome silent partner in many of those same places as a virtual tour guide.

The Downtown Cultural District is the latest local place to introduce recorded cell phone walking tours to give visitors a richer experience of its attractions. Today, the Pittsburgh Cultural Trust is launching the tour as part of its 25th anniversary activities.

The tour consists of 25 district "hot spots" -- identified by sidewalk markers and illustrated posters. Along the Liberty and Penn Avenue corridors, visitors can learn more about venues such as the Benedum Center, Heinz Hall, the Byham and Harris theaters, the new August Wilson Center for African American Culture, galleries, outdoor spaces and murals. The tour also spotlights Downtown development projects like The Encore on Seventh residential development, the David L. Lawrence Convention Center and the Renaissance Pittsburgh Hotel.

For those who remember what the neighborhood used to look like -- dotted with X-rated movie theaters, adult bookstores and other eyesores, the tour is a walk down memory lane designed to drive home the change that has happened over the past 25 years.

"Sometimes in quiet ways and sometimes in very big public ways, the Trust has helped to change the face of Downtown through the creation of the Cultural District," says Marc Fleming, Pittsburgh Cultural Trust vice president for marketing and communications. "What we're trying to do with the mobile tour and the audio tour is to put it all together -- by showing before and after pictures and providing behind-the-scenes information.

"There are a lot of fun facts and historical insights that are geared toward residents who have been around for the Cultural District's transformation. But also it's designed to reach those people who are visiting Pittsburgh for the first time."

Visitors and tourists call a number (412-235-6276), choose a location and listen to a short recorded segment about its background past and present.

Colorful sidewalk markers with questions are designed to pique curiosity about each "hot spot," such as this one at the Seventh and Penn Parklet ("How did this property go from selling love potions to inspiring a love for art?"). There are also posters at each site, illustrated with before-and-after shots.

Users can choose any or all of the options, tailoring the tour to their interests and time availability. "It has an element of spontaneity," Fleming says. Visitors can preview tour spots in advance from their home phones. They can also talk back, leaving comments and feedback.

There's no charge for the tours, except for the cost of the cell phone minutes used or roaming charges for out-of-town area codes.

There's an enhanced version of the tour for smart phones. Anyone with a 3G-enabled mobile phone can download a code that will launch a Web browser on his or her phone, which offers photos and links to other information.

The Cultural District walking tour will be available at least through the end of the year and the Trust's New Year's Eve First Night celebration, and possibly beyond.

Tour maps are available at kiosks in the Cultural District and at the Theater Square box office. They can be downloaded at the Trust's walking tour site (http://m.pgharts.org), which also has links to the background and descriptions for each of the hot spots.

The Cultural District cell phone tours are hosted by San Francisco-based Guide by Cell. Guide by Cell president Dave Asheim founded the company four years ago, inspired in part by his own disappointing experiences as a tourist. "I became frustrated with my museum and walking tour and garden experiences, because I couldn't find what I wanted to learn." That gave him the idea of turning the ubiquitous cell phone into a walking tour guide, with audio supplied by the attractions' staffs.

The company has produced audio tours for more than 550 clients in the United States, Canada and England, including the Museum of Modern Art in New York, the Library of Congress, several of The Smithsonian collections, the New England Aquarium, the Peabody Museum of Natural History at Yale, along with city walking tours and tours of historic houses. Phone numbers to connect to these tours are listed on the company Web site (http://guidebycell.com).

Locally, Guide By Cell hosts phone tours for The Andy Warhol Museum, Phipps Conservatory and Botanical Gardens, and the Carnegie Museum of Art.

The Museum of Art offered a cell phone tour of the last Carnegie International in 2008 and the response was good. "People enjoyed hearing the artist or curator talking about their works," said Ellen James, assistant director for marketing and communications. "It adds a richer experience."

The Warhol has been using cell phone tours for the past year. They get about 400 users a month, with the most popular features being the ones about the Jackie Kennedy and Silver Clouds series and Warhol Museum director Tom Sokolow­ski's introduction.

The Warhol also includes recordings made by visitors on its cell phone tours -- from celebrities to students and teachers -- in which they offer their perspectives on works shown there.

Now that cell phones are everywhere and minutes are cheap, they offer an easy alternative for tourists, Guide by Cell's Asheim says. "People don't want a heavy-duty, hour-long audio tour. Most people are just out for a stroll. There's no renting or paying for something. They see a sign and call this number.

"It's the convenience of just dialing and hearing that's so powerful."