Here is a pie chart showing the revenue of AAPL, MSFT, and GOOG in the latest quarter:
<br/>AAPL 81.80%, MSFT 52.86%, GOOG 76.69%<br/>
As we can see, Apple's revenue is the highest, followed by Microsoft and Alphabet C. Apple's revenue is mainly due to its hardware sales, while Google's revenue is mainly generated through advertising. Microsoft's revenue comes from a variety of sources, including software licenses, cloud services, and hardware.