SIPSTACK combines cloud PBX, business messaging, and AI call handling in one communications platform for businesses. Nova provides extensions, auto attendants, ring groups, call queues, call recording, voicemail-to-email with AI transcription, desktop and mobile apps, and IP desk phone support. Flare supports two-way SMS/MMS, messaging campaigns, automated replies, and built-in 10DLC registration from business numbers. Aura AI voice agents answer and resolve calls and provide transcripts, summaries, and sentiment analysis. SARA is an in-app assistant that makes account changes from plain-language requests. The apps are available for Windows, macOS, iPhone, iPad, and Android, and the platform also works in a web browser. SIPSTACK offers month-to-month subscriptions, free number porting, and a 14-day free trial.