As more and more websites become clogged with an excess of Flash effects, many internet users with iPhones and older smart phones can’t see the show.

Why? Because Flash effects don’t render on iPhones at all, and only minimally on smart phones manufactured prior to late 2009. (Flash Player 10, which is the full version of Flash that runs on PCs, is becoming available on smartphones running Windows Mobile, Google’s Android, Nokia S60/Symbian, and the new Palm operating systems. Devices with Flash Player 10 began to hit the market starting in early 2010.)

According to an article in CNET Review, “The company [Adobe] has worked for years on a lightweight incarnation of its Flash technology for mobile phones. Adobe executives said that about 40 percent of all phones that are shipped today use this version of its technology. But because Flash Lite doesn’t allow for the same functionality as what’s available on the Flash 10 desktop version of the technology, mobile users are missing out.”

If you are planning a website redesign, keep this in mind, and be sure to plan for alternate ways to display your most important information.

And if you are planning to purchase a smartphone or iPhone soon, be sure to check out the Flash capabilities before you buy. For a list of devices that currently support Flash technology, check this Adobe link.