The mobile Internet’s growth is a trend on par with the mass adoption of the personal computer, Cramer said.

Smartphones, which handle everything from voice to video to data, soon will be as ubiquitous as the PCs we now take for granted. This means that the related companies, and their shareholders, should see gains for many years to come.

To track the trend, Cramer created the Mad Money Mobile Internet Index, a group of 21 stocks at the heart of the industry. The index starts at 100, and its rise and fall will directly relate to how these companies – and the mobile Internet – fare.

Click ahead for a full list of the constituents.

Posted 18 Mar 2011

Note: Cramer is not rating all of these stocks as buys at all times. The index exists only to gauge his prediction that the mobile Web is tech's next big growth trend. And many of these picks are speculative, so readers must do their homework before buying, if they choose to do so. That being said, if smartphones continue their exponential growth as Cramer expects, then these are the companies that should benefit.

When this slideshow was published, Cramer’s charitable trust owned Apple.

The popularity of the Web's top search engine should carry over to mobile handsets, Cramer said. But he also likes Google's exposure to the ad industry. As the economy revs up, so does ad spending, and that's good for GOOG. But there's a double win here: Ad dollars are more and more moving online, which again is a positive for this company.

Before iPhone addicts there were CrackBerrys, a term of affection of sorts for users' compulsive checking of their RIM BlackBerry smartphone. While Cramer’s Mobile Internet Index is in no particular order, Research in Motion does play second fiddle to Apple in his mind. Still, the company is a major player in the space and therefore deserves to be included here.

Would a list of top mobile-Internet companies be complete without the maker of the revolutionary iPhone? Probably not. And that says nothing of Apple's ever more popular Macs and iPods. As of publish time, Cramer's price target for this stock was $400.

This and other infrastructure and delivery names are the foundation and nervous system of the mobile Internet, Cramer said.

This is the newest member of Cramer's mobile Internet index. The "Mad Money" host would only buy this stock on a pullback, though. Based in Bellevue, Wash., it provides the four largest wireless carriers in the U.S. -- AT&T, Sprint and T-Mobile -- with their mobile data platform. It operates Web portals for wireless providers, which allow customers with feature phones to access the mobile Internet.

Cramer has said he expects big things from Qualcomm, which develops digital wireless products and licenses them to equipment manufacturers. Every time a 3G phone that contains a QCOM chip is sold, the company collects a royalty. It’s a low-cost business with attractive margins, too. And with 3G penetration expected to increase, business should only get better. Qualcomm also supplies Nokia with chips for its smartphones.

Combination semiconductors are what really give Broadcom its edge. This technology allows Bluetooth, FM radio, Wi-Fi and a global positioning system, which would normally require separate chips, to be placed on just one. It’s a huge money-saving proposition, Cramer said, and it hasn’t yet been widely adopted.

Xilinx controls much of the multi-billion dollar programmable-logic-device, or PLD, market. Rather than being application specific, customers can reuse and reprogram PLDs at will. You’ll find them in high-end systems like routers, switches, base stations, servers, storage systems, radar and more.

This adaptability is a cost-effective benefit for Xilinx’s customers. They buy more to meet various needs and save money in the long run. Cramer likes this as part of a long-term, secular trend away from one chip with limited uses and toward another – Xilinx’s multiuse PLDs.

RF Micro, like many stocks on this list, is part of Cramer's “tech specs,” or smaller, riskier names that could offer more upside. Sure, investors can buy usual suspects like Apple or RIM, but why not go with a play that has more room to move? Cramer endorsed RFMD because the company is a huge beneficiary of the 3G wireless build-out, and as we know customer demand is high.

Following a few disappointing quarters, Cramer is not a fan of Cisco Systems. It is still levered to the mobile Internet index, however, because it provides foundation for the infrastructure and delivery systems.

In March 2011, the San Jose, Calif.-based company announced its first dividend of 6 cents, which represents a yield of roughly 1.4 percent.

Tessera operates in the semiconductor miniaturization business, reducing the space needed for chips and thereby making possible much smaller gadgets.

One product in particular allows for tiny yet better cameras in cell phones and computers. This technology shaves $2 off the total cost of the camera, and Tessera in return collects a 35-cent royalty. A number of companies are already licensing the product, Nokia among them, and Cramer sees the potential for virtually every other company climbing aboard as well.

NETL deals in “deep packet inspection,” which allows networks to filter data packets to prioritize the order in which they are sent. Put simply, the technology gets you quality video more quickly when you’re watching TV over the Web.

Another infrastructure and delivery play, Cramer is bullish on this Cambridge, Mass.-based company.

ARM is a leading semiconductor intellectual-property supplier, designing chip technology that is used in high-tech gadgets, including most of the world’s mobile phones. The company then licenses that tech out to the industry’s major players and collects royalties. Roughly five chips in every smartphone are based on ARM’s design and that number’s increasing as the mobile Internet continues to grow.

This company has a direct link with Apple’s hugely popular iPhone. Skyworks makes the power amplifiers used in 2G or 3G phones that speed up a wireless Internet connection, as well as high-performance circuits and semiconductors for both mobile phones and broadband markets.

Cramer likes this company for its local-number-portability technology, which allows customers to keep their phone numbers when switching cell carriers. Tekelec also produces equipment for transmitting text messages and managing voice traffic on wireless networks, another important part of the infrastructure needed to deal with the growing data overload.

This company's products help wireless networks handle bandwidth-hogging applications. That is key for meeting consumers’ demand for high-quality digital content.

Cypress operates a strong business in touch-screen technology for both cell phones and notebook computers. The top five handset original equipment manufacturers use the company’s winning designs, as does the Windows 7 laptop.

Much like Ciena, Tellabs is a speculative network-equipment maker that offers products and services to handle wireless voice, video and data transmission.

Cramer is bullish on this maker of power-management components for tech gadgets.

This Milpitas, Calif.-based company makes components for tablet. Due to the popularity of the iPad 2, JPMorgan recent stated that other tablet makers are seeing a slowdown. Cramer isn't concerned, though, because other electronics use flash memory and that's another component SanDisk creates.

You can now follow the Mad Money Mobile Internet Index, in real-time, by going to CNBC's mobile website. Using your smartphone's Internet browser, go to m.cnbc.com and click the Mad Money Mobile Internet Index link, right on the home page.