Voice conversational interfaces and real-time speech agents cover the stack that turns spoken language into useful, uninterrupted interactions: microphone capture, robust transcription, low-latency text understanding, persona-aware text-to-speech, and orchestration into multi-agent workflows. This topic spans consumer features such as ChatGPT Voice, Perplexity’s spoken answers, and experimental systems like BoldVoice, through to enterprise deployments in contact centers and CX automation. As of 2026, momentum is driven by several concurrent trends: open-source voice-language models and full‑duplex systems that cut round‑trip latency (e.g., Voila’s sub-200 ms real-time models), commercial TTS platforms offering studio-grade, multilingual voices and APIs (Murf AI), and enterprise agent platforms that combine orchestration, CRM integration, and no-code tooling (PolyAI, Yellow.ai, IBM watsonx Assistant). Practical applications include AI phone agents that answer or forward calls and book appointments (Simple Phones), real-time meeting assistants and conversation intelligence that produce transcripts, summaries, and action items, and personal AI assistants that blend voice with on-device privacy controls. Key considerations are latency, voice naturalness, multilingual coverage, integration with business systems, real-time transcription accuracy, and governance (privacy, compliance, and auditability). For buyers and builders, the landscape now requires choosing between open-source low‑latency stacks for custom, persona-driven experiences and enterprise platforms that prioritize reliability, orchestration and integrations. The result is a maturing ecosystem where voice-first interfaces move from novelty toward operational tooling for customer service, hybrid workplace workflows, and hands‑free personal assistants.