You can easily get Flappy Bird for your Android phone by just following these steps.
Before starting, you need to go to your security menu under settings and enable unknown sources.
Then open this link within your Android phone. It is automatically going to start downloading the .apk. Once downloading is done, you are going to get a notification. The name of the apk file might be different in your case.
Click on it to start the installation.
It’ll ask you how you’d like to complete action. Choose ‘Package Installer’ and click on ‘Just once’
Then following the steps, just like you’re downloading an app from Google Play store.
Voila! You can start playing Flappy Bird!