By Benjamin Pimentel, MarketWatch

Shares of Apple Inc. edged lower Monday as the tech giant kicked off its developer conference by unveiling a new version of its iOS operating system, while Broadcom rallied after the chip-maker said it's exploring whether to abandon the cellphone baseband business.

Apple (AAPL) fell 0.7% to close at $628.65 as the iPhone maker began its Worldwide Developer Conference, known as WWDC. Apple introduced iOS8, a new version of its mobile operating system. The company also unveiled developer kits geared toward the home and health care.

The tech sector got a boost from shares of Broadcom (BRCM), which were up 9.3% to close at $34.84. The chip company announced Monday that it was exploring the sale of its cellular baseband business, which is expected to cut expenses by $700 million.

But technology stocks took a hit from declining shares of Google Inc.(GOOGL), Hewlett-Packard (HPQ) and Facebook Inc.(FB) Google was down 1.3% to close at $564.34, while Facebook shed 0.4% to close at $63.08 and H-P fell 0.2% to close at $33.43.

The Nasdaq Composite Index (RIXF) slipped 0.1% to close at 4,237. The Morgan Stanley High Tech 35 Index (MSH) was off a fraction, while the Philadelphia Semiconductor Index (SOX) was up 0.5%.

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