### Answer
Vapi focuses on voice AI and provides functionalities for making and receiving phone calls; it doesn't directly support making calls to WhatsApp. Calls can be made directly to cell phones or through web calls [(1)](
) . Regarding the billing, Vapi charges a flat rate per minute for calls, prorated to the second [(2)](
) . If the call does not connect or is not answered, the duration and thus the billing would typically reflect the actual connection time, if any. For detailed billing practices, especially regarding unanswered calls, it's advisable to refer to the official documentation or contact support for the most accurate information.