Apple's Apple's Worldwide Developers' Conference kicks off on Monday and Apple's fans are hoping for an announcement of a new or cheaper versions of the popular iPhone.

Apple unveiled the 3G iPhone at last year's event but this year, Apple's CEO Steve Jobs will not be on stage still being on medical leave. Apple's iPhone is also facing the strong competition Palm's new Pre smartphone this year, which makes its grand debut on store shelves just two days before Apple's conference.

Speculation on a new iPhone has ranged from a model with a physical keyboard to handsets that boast more flash memory and faster processors. Many analysts believe Apple has a variety of new gadgets in the pipeline, from new iPhone models to a long rumored, so-called tablet mini-PC. Apple has officially said the conference will focus on important software operating system upgrades.

Users also expect the announcement of a more affordable $99 iPhone as well as the possibility of a model with a cheap data plan.

According to Apple, the new iPhone 3.0 operating system unveiled at the conference will include 100 new features, including the ability to cut and paste text and improved search functionality. Apple has also said it will showcase its new Snow Leopard operating system for Mac computers.