Case in point: messaging apps.

These are some of the most prolific drivers of dark social content sharing and referrals, but increasingly messaging apps are building functionality that could force marketers to engage with users in-app.

For example, Tencent-owned WeChat, one of the most popular messaging apps in China with more than 800m monthly active users, is currently testing a featured called Xiaochengxu, which translates to “little program.”

Xiaochengxu is a development platform for third-parties to build apps that operate within the WeChat app, effectively turning WeChat into an operating system of sorts.

As Forrester analyst Wang Xiaofeng told The Wall Street Journal:

With everybody coming in to launch Xiaochengxu, WeChat will be much more than an app. It will become the entry point of the Chinese mobile internet.

Currently, numerous companies, such as China’s Didi Chuxing ride hailing service, have integrations with WeChat, but those link out to their own sites from within WeChat.

Xiaochengxu could change that, ensuring that users never leave WeChat.

Hong Bo, a marketing consultant, says that’s WeChat’s goal. “The Chinese internet will be WeChat and others,” he predicts.

Already, some entrepreneurs and developers are expressing interest in Xiaochengxu, noting that being able to tap into WeChat’s user base could be beneficial and reduce their user acquisition costs.

Others, however, believe it’s “scary” that an app like WeChat could become the ultimate walled garden in which users spend all their time.

A sign of things to come?

Since the Chinese market for messaging apps is seen as leading Western markets, WeChat’s Xiaochengxu experiment is worth noting, as it could offer a glimpse of a trend that will eventually come to Western messaging apps.

Last year, Viber, which Japanese ecommerce giant Rakuten purchased for $900m in 2014, launched Viber Games globally.

Viber Games offers users a catalog of games that they can play from within the Viber app. Viber is popular internationally, and it’s worth noting that games are often one of the application types that are used to plant a walled garden.

For instance, when Facebook, which is the biggest walled garden on the internet, first launched its developer platform, many of the first Facebook apps that gained traction were games.

It’s also no surprise that Facebook is looking to extend its walled garden to its Messenger app through bots, money transfers and third-party integrations.

It may also be planning to build another walled garden with WhatsApp, the messaging app it purchased in 2014 for more than $16bn.

Walled gardens everywhere

While brands might be comfortable with the idea that messaging apps will become walled gardens – they are after all a part of the broader social market – the reality is that walled gardens seem to be growing eveywhere.

As Scott Eagle, the COO of 12 Digit Marketing, detailed in a post on InternetRetailer, major retailers and cable companies are also building walled gardens of their own, raising the specter of a day when brand marketers will have to be comfortable with the idea that it’s somebody else’s internet and they’re just living in it.