I am looking to write an app that receives pushed alerts from a server. I found a couple of methods to do this.
Firebase Cloud Messaging (FCM) is the new version of GCM. FCM is a cross-platform messaging solution that allows you to send messages securely and for free. Inherits GCM's central infrastructure to deliver messages reliably on Android, iOS, Web (javascript), Unity and C ++.
As of April 10, 2018, Google has disapproved of GCM. The GCM server and client APIs are deprecated and will be removed on April 11, 2019. Google recommends migrating GCM applications to Firebase Cloud Messaging (FCM), which inherits the reliable and scalable GCM infrastructure.
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