Concepts or coding lessons of Salesforce that you can implement easily

WhatsApp on Salesforce Integration in 5 Steps

WhatsApp's Click to Chat feature allows you to begin a chat with someone without having their phone number saved in your phone's address book. 
As long as you know this person’s phone number, you can create a link that will allow you to start a chat with them. 
By clicking the button, a chat with the person automatically opens. 
Click to WhatsApp Chat works on both your phone and WhatsApp Web.

1. Go to Setup -> Contacts -> Button and links
2. Click on New Button and Links button
3. Enter below required details:
Label: Click to WhatsApp Chat
Name: Click_to_WhatsApp_Chat
Display Type: Detail Page Button
Behavior: Display in New Window
Content Source: URL 



4. Use below URL in the text area:

https://api.whatsapp.com/send?phone={!Contact.Phone}&text={!JSENCODE("Hi "& Contact.Name &", Hope you are doing good. I want to connect with you regarding our new product.")}

5. Add this new button to the contacts page layout.

Now go to any contact which has correct phone number populated and click on Click to WhatsApp Chat button.

Note:
Use https://api.whatsapp.com/send?phone=whatsappphonenumber/&text=urlencodedtext where whatsappphonenumber is a full phone number in international format and URL-encodedtext is the URL-encoded pre-filled message.
Remove any zeroes, brackets or dashes when adding the phone number in international format. For a detailed explanation on international numbers, read this article.

You can use this functionality to any Salesforce standard and custom objects.