Nov 25, 2013 · 4 minutes

Messaging app Line, which got its start in Japan, has now passed 300 million users, about 100 million of which signed up in the last four months, according to a statement released by the company today.

On its own, this in't that big a deal: yet another press release trumpeting a user milestone. Except it's emblematic of a bigger change.

That's because Line’s recent growth mirrors fast growth among other messaging apps. South Korea’s KakaoTalk counts 110 million users. China’s WeChat claims 600 million. Kik, which is based in Waterloo, Canada, has reported more than 90 million registered users. (Note: These measurements are of registered accounts, which is very different to active users.) Meanwhile, going by the numbers, WhatsApp still looks secure. It recently passed 350 million active users.

But Line’s growth shows that WhatsApp is vulnerable. That’s because this new generation of messaging apps really aren’t just about messaging. They are mobile platforms.

Line has been making inroads not only in Japan, but also in Taiwan, Thailand, and Indonesia, and is fast picking up users in Europe and Latin America. A big push into the US, where its numbers have declined of late, is next on the agenda, Line has told The Next Web.

These messaging apps have adopted different strategies to WhatsApp when it comes to attracting and holding onto users. For Line, messaging is a front door to an experience that then opens up to include games, photosharing, stickers, and a de facto app store, which drives downloads of its other apps, including Camera and Tools. Kik is really just a mobile Web browser that hosts its own HTML5 apps, which third-party developers can now build. KakaoTalk has its own virtual eBay. And in China, people use WeChat to pay for physical goods.

The messaging part, which is ostensibly these apps' reason for existence, is actually an easily replicated commodity. It also happens to be all that WhatsApp has got.

The company has resolutely stuck to its singular vision of being an over-the-top messaging provider that works across platforms and devices. Even adding voice messaging, which Line, WeChat, and others have had for many months, was a big deal for the minimalist app. It makes money only by charging users 99 cents a year.

That’s not an impressive trick anymore. On my iPhone, I have a folder that contains six messaging apps. I use WhatsApp to chat with friends in the UK and Hong Kong, Kik to chat with friends in Canada and the US, WeChat to chat with friends in China, Line to chat with a friend in Thailand, Couple to chat with my girlfriend while I’m traveling, and Snapchat for sending compromising photographs to millennials. I also use iMessage a lot. (To communicate with friends in New Zealand, I still rely on carrier pigeon.)

With all these apps, I respond to a message when it is brought to my attention via a push notification. At that point, it doesn’t really matter where the message is coming from. I just tap on the notification and get taken to the relevant text-input field. On the other hand, when it comes time to write a message, I go to whichever app is used by the friend I happen to be trying to contact. Not one of these apps has a monopoly on my friends (yet), although there are some obvious regional biases.

As a heavy user of a variety of messaging apps, I see no clear distinction between what WhatsApp offers and what any of the others offer at their most basic level. For the messaging piece of the puzzle, the only difference is in user interface – and on that front WhatsApp is nothing to text home about. In terms of UI, it is inferior to Couple and Kik, and it’s just as ugly as the rest of them.

It’s also significant that this year, after a long period of not really saying anything to the media, WhatsApp, and perhaps some "people close to the company," have been aggressive with their PR efforts. In 2013, we have learned that it is not selling to Google (for $1 billion). And it is not selling to Facebook. There have been rumors that it is worth $2 billion. In a rare interview, CEO Jan Koum told AllThingsD’s Dive Into Mobile that WhatsApp is bigger than Twitter. Last month, Koum tweeted that WhatsApp users share more than 400 million photos every day.

Now, there could be a few reasons for WhatsApp being more active in its public relations. Perhaps it is looking to sell and wants to boost its valuation. Perhaps it’s looking to file for an IPO and therefore wants to tell a better story to the public. Perhaps it’s merely about ego: “Hey, we’re bigger than Twitter!” Perhaps, amid all the hype surrounding Snapchat and Twitter, it doesn’t want to get drowned out in the noise.

Or perhaps it sees a worrying trend with the rise of these other messaging apps and sees that by being a chat service without a platform it has backed itself into a corner.

One way or another, there’s little doubt that we’re going to hear even more from WhatsApp in the next 12 months. The question will be whether or not the headlines are always positive.