Very laggy interface. Review on Shazam

Recently I downloaded this application as my friend recomended this app to me. He told me that its a nice app for those who are music lover. So I download this app from playstore . This app is actually made to find any song name. Its like if I listen to any song and I really like that song but dont know about its name or singer name so at that time only this app will help in finding the name of the same. I used it several time in a week but its actually very laggy and sometimes it doesn't work properly even if I connected wifi as well. Even the user interface is so laggy and slow. Sometimes my phone gets hanged by opening this app. The idea of this app is quite innovative still lots of improvement is required. I cannot download any song from this app . If I shazam to any song I can only listen to that song from this app cannot download it . The app interface is not user friendly . This app is not upto the mark as I was expecting.