By Rieva Lesonsky

If you have one, you know teens are big spenders. In fact this demographic is a vital part of the economy. So it’s important to keep up with what teens want, what they’re buying and how they’re spending their time. Investment bank Piper Jaffray conducts in-depth research on the teen market twice a year. Last spring we reported that teens were changing their dining out habits. The “Taking Stock With Teens” survey for the latter half of 2014 reveals teen employment “improved modestly,” resulting in a rebound in spending.

Fashion had a particularly good 2014, with both teen boys and girls spending more on clothing. However, teens spent less on fashion accessories. Beauty spending increased, spurred by sales of “color cosmetics.”

You might think teens prefer to shop online, but you’re wrong, at least when in comes to buying clothes. While online shopping is up (as are mobile sales), teens still prefer to shop in-store. And when they do go online, they mostly choose sites associated with stores, rather than independent ecommerce websites.

But while fashion spending increased, Piper Jaffray reports, “Teen interest in food and electronics, at the expense of fashion goods, continues to be a strong underlying theme” for the past several years.

Not surprisingly, Apple is teens’ favorite electronic brand (of particular interest if your store is developing an app). Sixty-seven percent already own iPhones and 73 percent expect their next phones to be iPhones. Somewhat surprisingly, teens are eating more organic food at the moment.

The survey shows “friends and the Internet dominate teen influences.” Their social media of choice? Instagram and Twitter are the two most-used social media sites.

Rieva Lesonsky is CEO of GrowBiz Media, a media and custom content company focusing on small business and entrepreneurship. Email Rieva at rieva@smallbizdaily.com, follow her on Google+   and Twitter.com/Rieva.