Download -> http://bit.ly/knockappdown Knock, the simplest & most creative communication app. Vibration is indispensable system in the world. You can show to your friends own created vibration patterns! Knock communication with your friends just by vibration on the air. Knock is everything and anything, it all depends on you, the recipient and the time of the Knock. You say hello~? Just tap Knock! You say would you like something coffee? Just tap Knock! If when you are in danger, let your friends know using Knock. You can communication Knock to your friends anything, anywhere, anytime. Knock is vibration messenger that make a difference 'Yo' app. While 'Yo' may be similar to app, providing another convenient and practical dimensions. Knock’s possibilities are endless. Knock is 100% free & no ads. Best free communication messenger app in Google play!!! We don’t need your private information. Simple. Just input ID & Password, you can succeed Login. Knock is a swift to say whatever you wanna say to whoever you want to say it to. The new kind of chat for a generation that does not have time to waste. Anytime, anywhere you can send vibration to the other party! Have a picture you want to show your friends? You can send the URL to a friends through Knock. You sent URL by Knock, sent Knock your friends that you sent URL. Quickly invite a friends and enjoy together! Invite your friends by Facebook, LINE, Twitter, Kakaotalk, Tumblr, Pinterest, Instagram, Whatsapp, Snapchat, Vine, Yo, etc Social Network Service app. Meet the new communication space by vibration! We are still trying to provide a better service. Please attention that the growth potential for the future. Thank you so much. What are you waiting for? Start Knock!