Glossary

Key terms and concepts used throughout the AI companion app industry and on this site.

A

AI Companion: A software application that uses artificial intelligence to simulate a personalised companion. AI companions engage users through conversation, often with emotional intelligence and long-term memory features.

C

Character.AI: A platform allowing users to chat with AI versions of fictional characters, celebrities, and user-created personas. One of the most widely used AI chat platforms, with millions of community-created characters.

D

Dialogue Quality: One of Aether's seven rating dimensions. Measures how natural, contextually aware, and emotionally intelligent an AI companion's conversation is. Evaluated through standardised test scenarios covering casual chat and emotionally complex interactions.

L

Large Language Model (LLM): The type of AI technology that powers most AI companion apps. LLMs are trained on vast text datasets and can generate human-like text responses. GPT-4 and Claude are examples of widely used LLMs.
Long-Term Memory: A feature in some AI companion apps that retains information about the user and past conversations across sessions. Enables more personalised and relationship-like interactions over time. Nomi.ai is noted for its best-in-class implementation.

N

NSFW (Not Safe For Work): Content that is explicit or adult in nature. In AI companion apps, NSFW typically refers to sexually explicit conversation and image generation. NSFW features are usually age-gated and available only on premium plans.

R

Roleplay: A mode of interaction in which the user and AI companion take on characters or scenarios and interact within that fictional frame. Many AI companion apps offer specific roleplay modes with scenario libraries and character creation tools.

S

SFW (Safe For Work): Content that is appropriate for general audiences and does not include explicit material. SFW AI companion apps focus on emotional support, friendship, and romantic companionship without explicit content.

T

Turnstile: Cloudflare Turnstile is a CAPTCHA alternative used to verify that form submissions come from real users rather than bots. Aether uses Turnstile on its contact form to prevent spam.

W

Weighted Rating: Aether's overall app score is calculated as a weighted average of seven dimension scores. Dimensions considered more important (such as dialogue and privacy) contribute more to the overall score. Weights are publicly disclosed on our How We Rate page.