OTT is an acronym standing for over-the-top, covering a wide range of content delivered through applications and third-party services, whether they be video or audio. Over-the-top content can be accessed directly through an Internet-connected platform such as a PC, laptop, tablet, smartphone, and other web enabled devices. Over-the-top content is delivered without the aid of a service provider (AT&T, Comcast, etc). As such, the provider, although aware of the contents of IP packets being transmitted, is not responsible for, nor able to control the viewing abilities, copyrights, and/or other redistribution of the content. In essence, OTT services bypass those offered by a typically larger company which is neither the client, nor the benefactor (most of the time) in the exchange.
The most recognizable examples of OTT services are Skype and Google Voice, which operate and deliver VoIP services independent of a first-party service, like Nextiva. OTT services are a growing threat to fixed and mobile service providers, since they deal directly with end users over networks, completely excluding primary parties from all transactions.
Recently, OTT services have added text messaging (SMS), another major catalyst separating "carriage from content" with regard to first-party providers. As long as OTT exists as an alternative of content delivery, primary service providers will take strides to counter them with unique innovations not offered by emulators. The rise in OTT popularity is fueled by the fact VoIP service is reachable from any broadband IP connection on the globe, with Wi-Fi making high-speed Internet access even more accessible.