Question: Do you know of a chatbot that can handle voice conversations and integrate with various AI model service providers for advanced functionality?

Voiceflow is a full featured platform for building, launching and scaling voice AI agents. It's got a lot of features, including the ability to create a knowledge base, manage data centrally and integrate with lots of services like analytics tools and CRM systems. Voiceflow is good for automating customer support and building in-app assistants, and it's got pricing from free to enterprise deals.

Another good option is LobeChat, which supports voice and image interactions for building custom AI assistants. It can integrate with multiple model service providers like AWS, Google AI and Moonshot AI, and it's got plugins for a variety of domains. LobeChat has a free tier with basic models and more advanced options starting at $9.9 per month, so it's good for a range of budgets and needs.

If you want a more conversational and scalable option, check out Retell AI. The platform lets developers build human-like conversational Voice AI with features like complex workflow creation and sentiment analysis. Retell AI supports multiple languages and voices, and it's got a pay-as-you-go pricing model, so it's good for varying usage needs.