I have donloaded this whatsapp 2 years ago and using it without any problem . I have choose this product because we need only a phone number to registered other messanger we need to enter many things like email id . etc.
This is also easy to use and has many features and work any internet like 2g, 3g it can be also used in some featured phones it is popular and used by all accross the world I also take less storage.