Hi friend I am sayan.today I want to say about the negetive side of the whats scan application.no doubt it will be a good app for spying someone.it is the main problem for this app.this application only available for hack someones accounts at a single time.if you want to go for another accounts to hack someone whats app then the main problem is occured.because again and again scan the barcode is not always possible.so as per my point if this applications web sites designer kindly look after that matter.if atlist three to five whats app accounts will hacked in at a time then it will be the best application for all of viewers