To say the least, it’s an interesting time for museums worldwide. While attendance remains steady, endowments and contributions have shrunk, forcing some museums to pursue layoffs and others to close down altogether. But an innovative move onto cell phones and PDAs could perhaps salvage the world’s museums by expanding their reach.

The most prominent shift into the mobile space came courtesy of London’s historic National Gallery, who last week released a new iPhone mobile app giving iPhone users instant access to 250 of the gallery’s most iconic works, including paintings from Botticelli, Renoir, and Van Gogh, as well as 200 minutes of additional audio-video content. Targeting hard-core art enthusiasts, the National Gallery is the first major museum to provide such an app, which also offers works grouped together in a dozen separate themed tours. With the National Gallery on board, the exploding handheld industry could become a popular destination for the world’s museums.

The fascinating trend began really taking flight in May, when the Brooklyn Museum released its own iPhone app. Promising an API that would expand over time, the Museum made much of its collection open to iPhone users. The innovative free app almost immediately drew rave reviews from the art and tech communities alike. Shortly after the Brooklyn Museum app took off, the Santa Barbara Museum of Natural History introduced its own mobile app to help publicize its Butterflies Alive! exhibit. The app featured a number of photographs from the exhibit and provided interactive content, like a digital guide to the exhibit.

Even big-time art dealer Christie’s has just launched its own mobile app, allowing users to appraise their own items, view lots available for auction, and even follow live auctions online.

Other institutions throughout the world are likely to jump on the mobile museum trend in the coming months: it's a novel way to expand a collection's reach at a time when museums need it most.