WA Promotion is an online platform that allows businesses to send promotional text, image, and audio messages over WhatsApp to customers and clients. Key features include adding multiple sender IDs, importing unlimited contacts, sending messages individually or in mass campaigns, and receiving reports on message delivery. Credits are used to send different types of messages, with image and audio attachments each costing 2 credits and 160-character texts costing 1 credit. The service aims to help companies better promote their brands and products using the popular WhatsApp messaging platform.