Mary Meeker, a venture capitalist at Kleiner Perkins Caufield & Byers, released her 21st annual report on the biggest trends in technology and the Internet on Wednesday. The report covers a wide swath of issues, from slowing smartphone sales to photo sharing and online advertising.

Here’s a quick take on some of the most interesting findings.

1. Mobile ads will grow by tens of billions of dollars in the coming years -- and will mostly line the pockets of Facebook and Google.

The two Silicon Valley giants account for 76 percent of all U.S. Internet advertising. Google’s share of the pie is far...