here is a PHP based solution to use a webbased solution, for a given  numbers. and since then its become a hot topic, and people  started to use it as mechanism to do telemarketing. earlier in FEB whatsapp tried to enforce GITHUB to remove all whatsapp related close . click this link. From what I could gather on their Github, the came to an arrangement with WhatsApp, and as such they will not sue WhatsApi if they respect their network. So on September 29th, the put back the source code online:

The question arise is why whatsapp is not taking any action against them.

How whatsapp can  block websites

If I say In a layman’s terms . To do this whatsapp has to change the mobile application logic and add some extra secrete information, which is not possible by website. and thats only possible if  latest version of the whatsapp is reached to each and every mobile users. which is very very distance possibility. and until then whatsapp can not at all do  anything. it must allow website to interact with whatsapp server.

The point here to understand is that whatsapp is not helpless. As per my understanding any gratuate student build a logic by which, block all he web-solution and even other mobile app to interact with whatsapp server. and many websites API are already there in market including Facebook,twitter etc,which allows API to be used only to registered application. and whatsapp has not done anything so far.

what is the impact of whatsapp blocking the websites

most probably whatsapp, will have provided a paid API. and even if that is not provided, then the only option is to move to real whatsapp application. I means move out Master number to a real phone and run whatsapp there. in nutshell its not a serious  breakdown, just moved to a manual procedure.

why whatsapp should not block customer service.

I think genuine customer service, can be unique selling feature of whatsapp. in the tough competition against upcoming chat applications.Rather then taking a stiff path, whatsapp can think of generating revenue in future rather then completely blocking it. and hence whatsapp should not block the API.

whatsapp is fishing spammers.

may be whatsapp is understanding its USP, as  written above. or may be its  waiting for its latest version to reach 80% of mobile. whatsoever it is, but as of now it seems like whatsapp has decided to strenthen its server logic to identify spammers and allow genuine  customer service. its the same path that google serch engine is doing to promote genuine pages. Thats  bad news for spammers.

What is genuine customer service.

Customer service is not a spamming, and if followed good practice it much not get blocked, because here both parties are happy.

Particularly in our  case we doubly make sure that

(1)customer has your  numbers in his contact list.

(2) one of the number is a master number , and it will not be used for bulk messaging.

(3)You can also try to add customer name in the message. so each message is unique and personalised.

(4) ask user to send STOP message rathe then blocking you.

(5) to be more precise we can build a policy of promoting communication only on master number. which means, the non-master server number upon receiving any query from client will, shift the communication to master number. this way customer will get aquintend with master number.

(6)in case of any un-predictable decision to block such mechanism, can still be moved to a manual.

Is it legal to use  whatsapi or any unconventional solution.

yes, it is legal to use WhatsAPI,Now for the story, it looks like the initial threats from Whats App to sue WhatsAPI were caused by people using the service for spam, and as such WhatsAPI got a cease and desist letter from WhatsApp lawyer.