Of all the technologies developed by Terragens throughout history few have been as significant, or as mundane, as the exoself. Rather than a single technology or protocol the term "exoself" is used to describe a wide range of software add-ons linked to the mind in a cooperative way; supplementing, enhancing and augmenting capabilities as desired. The basic physical technologies of an exoself consist of a DNI and an exocortex. The scope of an exoself's use is vast. At the lower end it can run programs that interface with the user via augmented reality; providing everyday functions such as net access, entertainment, communication, implant control, document creation etc. High level functions involve integrated neuromods that seamlessly blend with the mind; common uses of this extreme include polyglot modules, innate calculative abilities, memory boosters, pattern analysers and many more intelligence amplifying features.
Exactly how invasive an exoself is is mostly up to the user. More integration between mind and software lead to greater synergy and ability but at the potential cost of alterations in personality and toposophy. Heavily modded individuals may find it difficult to live their previous life, especially socially, due to this shift in personality. Less integration can be less efficient but leaves the user in a relatively unburdened executive role. Generally speaking there are three popular approaches that most exoself users employ to a lesser or greater extent;
Full connectome integration. The software packages (neuromods) of the exoself are seamlessly weaved into the user's natural connectome, expanding their mind well into their exocortex. The various installed modules become part of the user's thoughts, feelings and conscious experience. Especially with continual use it becomes difficult, even meaningless, to determine where the mind ends and the exoself begins. This approach is a necessary step for those wishing to ascend, as such it also holds the most risk. Practitioners must be wary of any number of dangers from neuromod induced cognitive disorder to accidental, failed ascension leading to a blight/perversion.
Augmented perception interface. Via the DNI the exoself interacts with the user through modulation of their natural sensorium and mental state. Information is presented in a variety of ways from customised visual/audial icons floating conveniently in front of the user's face to synthetic evocations ranging from artificial instinct prompts to transcendental experiences. Common input methods include subvocalisation and "gestural intent" in which vague desires to activate, close or otherwise manipulate a virtual icon leads to a response. Ultimately the interface adapts to the user, providing the optimum diversity of I/O media.
Virtual servitor. The totality of the exoself is consolidated as one or more discrete personas. In essence the exoself becomes a non-sophont individual that the user can interact with as they would any real sophont. Generally communication is via subvocalization and augmented reality though in some cultures a physical manifestation is prefered. An exoself acting as a servitor is often described as a life companion, an entity that one can have a useful relationship with rather than merely being an interface layer. Throughout history the popularity of one persona over many has waxed and waned (according to recent surveys groups are fashionable in the sephiroitics). In a group system different personas can be created to specialise in providing different exoself functions, for example: an archetypal scholar for memory retrieval, a stoic bioengineer for implant control, an exuberant socialite for narcogram regulation etcetera. A not insignificant number of terragens were 'born' through the deliberate (or in rarer cases: accidental) gifting of sophonce to an exoself persona.
Regardless of the specific configuration individuals and societies choose to adopt exoself technology has significant influence over the daily lives of Terragens. With them victims of brain damage can simply upload a prosthetic and continue life uninhibited as their natural brain heals, Simmwalkers and other toposophic explorers can further develop their lifestyle, and with a suitable mentor all modosophonts can utilise their exoself as a platform for ascension.