
<p>On a recent Saturday, Johan Dijkland, a 23-year-old student in Emmen, Netherlands, opened a free messaging app called Line on his iPhone. Then he tapped on a virtual sticker of a sleepy panda with a "good night" speech bubble and pressed send to a friend.</p><p>With that action, Mr. Dijkland's text joined the tens of billions of messages that are processed every day from a fast-growing crowd of mobile messaging apps.</p><p>These messaging appswith funny names like WhatsApp, WeChat and KakaoTalkhave become an indispensable form of communication for hundreds of millions of people world-wide.</p><p>They are also rankling technology giants from Silicon Valley to Seoul. That is because when users like Mr. Dijkland send messages using Line, his mobile carrier Vodafone Group PLC and iPhone maker Apple Inc. don't directly profit from the interaction.</p><p><a href="http://online.wsj.com/article/SB10001424127887323466204578382733261211950.html">Keep reading...</a></p>