Ask HN: API/service for pushing text notifications to android/iOS

Hello HN! I am looking for a API/service similar to PushBullet that I can use to send plain old text to devices that have subscribed/installed an app. The reason I ask is that I am working on a ruby script that checks an API and lets users know when it has been updated. see https://www.pushbullet.com/channel?tag=metacritic-new-albums.

Thanks!