Complex sentence: CallFire designs, develops, and offers web-based VoIP products and services as a business-to-businesses (B2B) service for small and medium sized-businesses (SMB's) and bills customers based on usage.
Split into simpler sentences: CallFire designs, develops, and offers web-based VoIP products and services. The company offers and markets its products as a business-to-businesses (B2B) service for small and medium sized-businesses (SMB's) and bills customers based on usage.