Jeremy Hobson: We’ll get a look today at how the tech sector is doing. Google will report its quarterly earnings after the stock market closes. The company has been doing a lot of spending lately on new businesses and technology. But how much money is coming in from Google’s bread-and-butter business — those ads it sells next to search results?

Marketplace’s Queena Kim reports.

Queena Kim: Like just about everything in tech these day, it’s all about “mobile,” which is fast becoming the way we search online.

Benjamin Schacter is an Internet analyst at Macquarie Research.

Benjamin Schacter: We think right now that somewhere between 12 and 15 percent of all searches are happening on mobile devices and by the end of just 2012, you’re likely to see that number move to 25 to 30 percent

For Google, that trend is a mixed blessing. The company’s mobile business is growing but mobile ads bring in less, per click, than search ads on a computer. Google said its “revenue-per-click” was down 8 percent last quarter.

Colin Gillis is a tech analyst for BGC financial. He says there are some things people jsut don’t buy on cell phones.

Colin Gillis: Not many people are willing to buy a car or purchase an airline ticket necessarily from their smartphone.

Google also gives a cut of its sales to companies like Apple in return for making it the search engine on iPhones and iPads.

Analysts say Google could boost its mobie ad revenue if its investments in social media and mobile pan out.

I’m Queena Kim for Marketplace.