android dosnt' work

Hi guys i would install the plugin notification on my website to push the post on the android device. I had configurated all! For android device,i create a project to GCM and i put the api key but i think that i miss something steps. Moreover i dont’ know what insert into schema url!

For GCM shoul i insert something codex into my app?

https://ww.wp.xz.cn/plugins/push-notifications-for-wp/