In a world where the smartphone is becoming the new television, billionaire investor Mario Gabelli says the best way to make money in media is by investing in the content itself. 

That means investing in the "ignored and unloved" traditional media giants, media distribution companies and live sports entertainment firms, said Gabelli, the CEO of GAMCO Investors Inc.  (GBL) - Get Report , on Wednesday at the Yahoo Finance All Markets Summit in New York City. It also means thinking on a global scale, from Bollywood to Hollywood, Gabelli argued. 

"We're looking at the whole ecosystem," Gabelli said. "I have a simple concept. Whatever you see on any device at any time anywhere in the world," Gabelli said you should pay attention to who created it and who's distributing it.

Specifically, Gabelli says he likes Viacom Inc. (VIAB) - Get Report , Sony Corp. (SNE) - Get Report , Vivendi SA (VIVHY) , Verizon (VZ) - Get Report and the Madison Square Garden Company (MSG) - Get Report . He dodged the idea of investing in Pandora (P) or Spotify (which is rumored to be pursuing a non-traditional IPO by late 2017 or 2018); instead, he said people should buy the companies that possess the content libraries. 

"That would be a Vivendi or a Sony," Gabelli noted. "We like Sony for a lot of reasons. AI, robots, VR but also their content." 

Gabelli called Viacom a "bargain" that has more room to run under its new CEO, Bob Bakish. Viacom could also benefit from selling non-U.S. assets in places such as Argentina, India and England as part of a package, ultimately reducing debt. Viacom, which was trading down 1.3% to $25.31 on Wednesday, is a buying opportunity at $26 a piece, Gabelli added. 

Aside from content creators and distributors, Gabelli said he's also investing in companies such as Verizon, which he believes are at the forefront of the 5G revolution. Countries are gradually upgrading to a 5G mobile networks, which promise to make it faster and easier to download and view content on mobile devices, among other advantages.  

Nearly all the big telecommunications companies, including Verizon, AT&T (T) - Get Report , Sprint (S) - Get Report and T-Mobile (TMUS) - Get Report have been eager to buy up spectrum on a global basis. Verizon in May agreed to acquire spectrum holder Straight Path Communications for $3.1 billion, ending a fierce bidding war with AT&T.  

"Verizon will be one of the leaders in this space," Gabelli noted.

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