Ok, i found the button. Now my problem is a bit different.
My desktop site is also mobile optimized - and I want to show the button only when the mobile browser is used. It links to the app store on Google play.
However my app also pulls content from my website and I dont want to show the button there. As the user is already using the app. But currently its showing - how to block that ?
One more issue - the button shows perfectly on website but a round button/ base shows below when clicked.