Apple Inc. (NASDAQ:AAPL) investors have high hopes the Cupertino-based tech giant will soon release a smartphone with a larger screen. Unfortunately, investors still have a few concerns involving the company thanks to an upcoming book that shines a negative light on the smartphone maker.

iPhone 6

Larger phones in the works

ISI Group analyst Brian Marshall shared a note speculating iPhone 6 will feature a larger screen that is found on many Android smartphones. He sees the company releasing two larger phones and many Android users switching back to Apple.

Marshall points out the iPhone installed base has about 260 million users. All of that was equivalent to the last seven quarters’ worth of iPhone sales and about half of those numbers are upgrades. Overall, roughly 9% of all iPhone users upgrade to the current model in the average quarter. However, Marshall thinks that number has dropped since the iPhone’s market has grown to 11% in 2011 and 2012.

Published book sheds negative light on Apple

The recently published book Haunted Empire: Apple After Steve Jobs, which was written by Yukari Kane (former Wall Street Journal reporter), goes into detail on how Apple’s best days are in the past. The company’s chief executive officer Tim Cook spoke to CNBC and made the following statement:

“This nonsense belongs with some of the other books I’ve read about Apple. It fails to capture Apple Inc. (NASDAQ:AAPL), Steve, or anyone else in the company. Apple has over 85,000 employees that come to work each day to do their best work, to create the world’s best products, to put their mark in the universe and leave it better than they found it. This has been the heart of Apple Inc. (NASDAQ:AAPL) from day one and will remain at the heart for decades to come. I am very confident about our future. We’ve always had many doubters in our history. They only make us stronger.”

Investors are also disappointed with Apple TV. There were numerous rumors of an actual television set which would integrate with all Apple Inc. (NASDAQ:AAPL) devices, however such device has yet to surface.