Whatsapp is a widely used application on mobile phones nowadays. The reason is that you can communicate with anyone anywhere in the world without paying a cent for SMS services to your network provider. Due to this businesses should not ignore people visiting their websites using mobile devices and provide an option to people to communicate with them on Whatsapp.
Here I will show you how to send a message to a Whatsapp application on an Android phone from a web page.
Suppose your web page has the following code to contact via Whatsapp.
Now replace the above code with the following one
Of course the above code will only work if the visitor is browsing on a mobile device and has Whatsapp installed other wise it will not work.
I hope the above helped.