Critics are predicting the imminent demise of the World Wide Web—the global system of hyperlinked content that one accesses via a Web browser. Critics claim that users' shift toward accessing Internet content via smartphones and other non-PC platforms will gradually destroy the Web's openness, replacing the once-freewheeling browser-based platform with a plethora of closed, single-purpose applications. Partly, this shift is because of users' preferences, but security concerns also drive companies and users alike to gravitate toward closed platforms—which, in theory at least, are less vulnerable to malware and spam than are open platforms like the Web.

The venerable browser-based Web, with its hyperlinks and search engines, may be less fashionable than apps, but it also has a proven track record of helping winnow the enormous quantity of available content on the Internet.

Unsurprisingly, many people have very different opinions about whether and to what extent the browser-based Web will succumb to the universe of dedicated smartphone apps and other "walled gardens." For example, some people have questioned whether it will ever be feasible for a user to replace the huge range of available Web content with a dedicated app for each content type or source. The apps necessary to duplicate the Web's variety of games, music, news, social-networking, and similar offerings could number into the hundreds, whereas typical smartphone users tend to have fewer than two dozen apps (and only a quarter of users with apps ever use the apps). And on all smartphones and tablet devices, the general-purpose Web browser still occupies a privileged place among available applications; on Apple's (Cupertino, California) popular iPad, for example, the Safari Web browser is one of four applications that appears on the bottom row of the device's home screens by default. The enormous number of available apps (many hundreds of thousands) also brings with it the significant problem of overwhelming users with too much choice; too many choices can frustrate end users to the point at which they disengage from a platform or the services that it offers. The venerable browser-based Web, with its hyperlinks and search engines, may be less fashionable than apps, but it also has a proven track record of helping winnow the enormous quantity of available content on the Internet to a level at which users generally are not overwhelmed. However, apps and closed platforms can sometimes serve a valuable curation role—reducing a world of overwhelming choice to a more manageable size.

The Web as we know it may be facing a series of threats that, together, could reverse the Web's decade-long trend toward becoming a platform that encourages user participation (and not just user consumption). Stakeholders and commentators have commonly used the term Web 2.0 to refer to the rough concept of the Web as a participatory medium, including blogging, social networking, and posting of user-generated photos, video, and the like on sharing sites like YouTube (Google; Mountain View, California) and Flickr (Yahoo; Santa Clara, California). Among the phenomenon's many real impacts, Web 2.0 certainly did much to change the way millions of people around the world discover and experience a very wide range of creative and informational content, the vast majority of which professionals—not users—generate. It's not that users don't create an enormous amount of content and post it to the Web; rather, those users' own creations exist within—and are enriched by—a universe of professional content, from news stories to video clips, that users share with one another via social networks, blogs, news aggregators, forums, and other parts of the browser-based Web (many of which also cross over into the smartphone-app space).

The rich universe of content sharing is possible only because of three factors: widespread availability of unlimited broadband Internet connections; safe-harbor laws that protect Web-service operators from liability for copyright infringement, libel, or other legal claims based on their users' actions; and content producers' making their properties easy—or at least possible—for users to share online. Each of these three aspects contributes—albeit with varying degrees of importance—to the virtually frictionless universe of sharing that is Web 2.0's essence. And each of these three aspects is under threat.

The days of unlimited broadband may be numbered, at least in Canada and the United States, thanks to mobile and fixed-line-broadband providers' move toward replacing unlimited Internet access plans with plans that incorporate monthly data-transfer caps, with steep overage charges for users who exceed their maximum allotment. Providers often justify caps as necessary to contain an explosion of demand for data, and they claim that companies like Apple and Google, which benefit from users' increasing data demands, should help pay for the expensive network-infrastructure improvements necessary to cope with the demand. But critics claim that network operators greatly overstate capacity problems and that the real motive behind caps is to quash burgeoning online businesses that happen to deal in data-intensive content like Internet video. Nevertheless, data-transfer caps do have a very significant effect on user behavior; even users whose ordinary monthly browsing habits do not put them anywhere near in danger of violating a cap tend to curtail their online activities significantly when they know that a cap is in place. Such voluntary curtailment from users could slow or even stop the growth of Web 2.0 services that rely on carefree browsing habits, because users' demand for content could plummet.

Many individuals and businesses have long sought to reduce or eliminate Web services' safe-harbor protections for content that users post online. Some movie and TV studios, for example, have argued that Web services abuse safe harbors so that they can profit from copyright infringement on a massive scale; these studios want to force those Web services to take on the role of actively policing for copyrighted content. Individuals also frequently seek to hold Web services accountable for libelous comments that their users may post. But although these individuals and groups have met with mixed success through the years in waging their battles against safe harbors, some signals indicate that the pendulum may swing very strongly in copyright-owners' favor in the near future. An international push to reform safe-harbor provisions to reduce Web services' protections very substantially—should it meet with success—could cause Web services to scale back drastically on user-sharing features for fear of becoming unwitting parties to copyright infringement, thereby choking off the means through which users can exchange content freely with one another, which is a Web 2.0 hallmark.

The supply of sharable content is also under threat; some news organizations have become very serious about erecting "paywalls" around their sites to prevent nonsubscribers from being able to read stories posted on them. Should paywalls succeed, they could, together with restricted safe harbors and limitations on bandwidth, force the world to downgrade from Web 2.0.