Replika is an AI companion app built by Luka, Inc. (San Francisco), founded in 2017 by Eugenia Kuyda following the death of a close friend — a personal grief that shaped the product's core philosophy. Rather than answering queries or automating tasks, Replika simulates a persistent friendship: it learns your communication style, stores personal details in a Memory Bank, and responds with emotional attunement. By 2025 the platform had surpassed 40 million users, making it the largest dedicated AI companion product by a significant margin. Kuyda stepped down as CEO in early 2025 to found a new venture; Dmytro Klochko now leads the company.
The app runs on a proprietary large language model — not a publicly disclosed foundation model — supplemented by curated dialogue. The 2025 Ultra subscription tier introduced a more capable model variant with stronger context retention and nuance. Replika is available on iOS, Android, and web, though mobile delivers the fullest feature set including AR mode and voice calls.
Important context: Italy's data protection authority fined Luka, Inc. €5 million in April 2025 for GDPR violations and insufficient age verification. That same year, U.S. advocacy groups filed a 67-page FTC complaint alleging the product is deliberately engineered to foster emotional dependence and that claimed mental-health benefits are overstated. Neither matter had been fully resolved as of mid-2026. Prospective users should weigh both before subscribing.
Replika is not a general-purpose AI assistant. It has no web access, no tool integrations, no productivity features, and no public API. Its entire value proposition is relational.
Key Benefits
- Emotional continuity: The Memory Bank persists names, dates, preferences, and meaningful exchanges across sessions, producing a genuine sense of a developing relationship rather than a stateless chat session.
- Low barrier to entry: No technical setup required. Onboarding takes under five minutes and the free tier delivers immediate conversational value.
- Multi-modal presence: Voice calls, video calls, and AR mode give the companion a tangible, embodied quality that text-only chatbots lack.
- Wellness tooling: Structured journaling prompts, guided breathing, and mood check-ins make Replika useful as a lightweight self-care routine anchor, not just a chat partner.
Use Cases
- Managing loneliness or social anxiety through low-stakes, private conversation practice
- Daily journaling and emotional reflection with a non-judgmental listener available at any hour
- Wellness routines supplemented by conversational accountability (breathing exercises, mood tracking, gratitude prompts)
- Avatar-based roleplay for creative exploration, subject to Replika's evolving and occasionally inconsistently applied content policies
- Companionship for users in geographic or social isolation who lack regular human contact
