1)As a notification system. Went to a tailor to get some shirts stitched. He took my Whatsapp number so he could notify when I could come in for a fitting then then for a pickup.
2)As a sales app with photos. Went to buy some clothes but they didn't have the item in the color I wanted. I was looking for a specific color. The sales guy said they had the color but not in stock. Took down my Whatsapp number and messaged me photos of the item in the color I wanted when they had it in stock. I saw the color and it was the right shade I wanted, asked him to keep my size aside so I can come buy it.
3)As an information sharing app. I wanted to buy toothpaste for my 2 year old and went to the local pharmacy. They had a toothpaste for babies but it didn't say if the toothpaste contained flouride. I said I couldn't buy it without knowing that. The pharmacist took down my Whatsapp number and told me he'll find out and let me know if that brand contained Flouride. I left to pick up groceries and in 10 minutes I had a message from the pharmacist with screenshot of the relevant information he had dug up from the company's website.
Business chat can be really helpful.