update README

Author: tibbi

README.md

@@ -6,6 +6,8 @@ A textfield for adding quick notes with a customizable widget.
 Need to take a quick note of something to buy, an address, or a startup idea? Then this is the app you've been looking for!
 You can access the note in no time by using the customizable and resizable widget, which opens the app on click.
 
+<a href='https://play.google.com/store/apps/details?id=com.simplemobiletools.notes'><img alt='Get it on Google Play' src='https://play.google.com/intl/en_us/badges/images/generic/en_badge_web_generic.png' height=60/></a>
+
 <img alt="App image" src="screenshots/app.png" width="250">
 <img alt="App image" src="screenshots/widget_config.png" width="250">
 <img alt="App image" src="screenshots/widget.png" width="250">