More than three months into a medical leave from Apple Inc., Chief Executive Steve Jobs remains closely involved in key aspects of running the company, say people familiar with the matter.

Chief Operating Officer Tim Cook runs the day-to-day operations at Apple, these people say. But Jobs has continued to work on the company's most important strategies and products from home, they say.

He regularly reviews products and product plans, and was particularly involved in the user interface of the new iPhone operating system that Apple unveiled last month, these people say.

Apple co-founder Jobs, who is considered the company's creative leader, is also involved in the development of future projects, they say.

People privy to the company's strategy say Apple is working on new iPhone models and a portable device that is smaller than its current laptop computers but bigger than the iPhone or iPod Touch.

Jobs, who was treated in 2004 for a rare form of pancreatic cancer, took a medical leave in early January, saying he would return in June and would remain involved in "major strategic decisions while I am out."

But he has made no public appearances or statements since then, and it has been unclear just how involved he continued to be. Apple has been mum about how Jobs's absence is affecting daily operations.

Jobs didn't respond to requests for comment. Apple spokesman Steve Dowling said: "Steve continues to look forward to returning to Apple at the end of June."

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