This is what Steve said -
On the naming of Apple, he said he was “on one of my fruitarian diets.” He said he had just come back from an apple farm, and thought the name sounded “fun, spirited and not intimidating.”
Now coming to second part -
Apple's first logo, designed by Ron Wayne, depicts Sir Isaac Newton sitting under an apple tree. It was replaced by Rob Janoff's "rainbow Apple", the now-familiar rainbow-colored silhouette of an apple with a bite taken out of it. Janoff presented Jobs with several different monochromatic themes for the "bitten" logo, and Jobs immediately took a liking to it. However, Jobs insisted that the logo be colorized to humanize the company. The logo was designed with a bite so that it would not be confused with a cherry.