我找不到我在哪里读到它，但我相信gmail利用一个开放的TCP连接来执行电子邮件推送。

如果你可以依靠谷歌库来满足你的目标市场，那么你可能想要依靠GTalk的功能(在现有的用户名上注册一个资源-当消息进入BroadcastReceiver时拦截它)。

如果不能，而且我希望您不能，那么您就需要捆绑您自己的XMPP版本。这是一个痛苦的过程，但是如果XMPP单独捆绑成一个独立的库，就会容易一些。

你也可以考虑PubSubHubub，但我不知道它的网络使用情况。我相信它是构建在XMPP之上的。

我最近开始在Android上使用MQTT http://mqtt.org，作为一种实现您所要求的方式(即不是SMS，而是数据驱动，几乎是即时消息传递，可伸缩，而不是轮询等)。

我有一篇关于这方面的背景信息的博客文章http://dalelane.co.uk/blog/?p=938

(注意:MQTT是IBM的技术，我应该指出我为IBM工作。)

我一直在研究这个问题，jamesh推荐的PubSubHubBub不是一个选项。PubSubHubBub用于服务器到服务器的通信

"I'm behind a NAT. Can I subscribe to a Hub? The hub can't connect to me." /Anonymous No, PSHB is a server-to-server protocol. If you're behind NAT, you're not really a server. While we've kicked around ideas for optional PSHB extensions to do hanging gets ("long polling") and/or messagebox polling for such clients, it's not in the core spec. The core spec is server-to-server only. /Brad Fitzpatrick, San Francisco, CA Source: http://moderator.appspot.com/#15/e=43e1a&t=426ac&f=b0c2d (direct link not possible)

我得出的结论是，最简单的方法是使用Comet HTTP push。这是一个简单且易于理解的解决方案，但它也可以用于web应用程序。

看看Xtify平台。看起来他们就是这么做的，

As GTalk is gone from the SDK, it might be a good idea to make a 'standard' push messaging system. That way, only one service has to run, only one extra tcp connection needs to be open. Applications should talk to this service using Intents and should first request permission to send and receive notification from the service. The service should then notify the user a new application wants to send and receive messages. The user will then grant or deny permission, so he stays in control. The application will then register an action + category to the service, so the service knows how to deliver the pushed message.

这到底是不是一个好主意?

Why dont you go with the XMPP implementation. right now there are so many public servers available including gtalk, jabber, citadel etc. For Android there is one SDK is also available named as SMACK. This we cant say a push notification but using the XMPP you can keep a connection open between client and server which will allow a two way communication. Means Android client and server both can communicate to each other. At present this will fulfill the need of Push in android. I have implemented a sample code and it really works great

有一个新的开源项目正在开发一个Java库，用于Android上的推送通知，使用Meteor comet服务器作为后端。你可以在执事计划博客上查看。我们需要开发人员，所以请传播这个消息!

Firebase Cloud Messaging FCM FAQ是GCM的新版本。它继承了GCM的核心基础设施，可以在Android、iOS和Chrome上可靠地传递消息。但是他们会继续支持GCM，因为现在很多开发者都在使用GCM sdk来处理通知，而客户端应用的升级需要时间。

截至2012年6月26日，谷歌云消息传递是向设备上运行的应用程序发送消息的首选方式。

以前(现在已弃用)，该服务被称为“云到设备消息”。

我最近开发了http://pushdroid.org，它是一个单一的应用程序，应该安装在手机上，就像谷歌已经在2.2中实现了它，从1.5开始工作，并通过意图广播。

XMPP是一个很好的解决方案。我在一个支持推送的、实时的Android应用程序中使用过它。XMPP功能强大，高度可扩展，易于集成和使用。

有很多免费的XMPP服务器(尽管出于礼貌，您不应该滥用它们)，还有一些开源服务器可以在您自己的机器上运行。OpenFire是一个很好的选择。

你想要的库不是上面提到的Smack，而是aSmack。但是请注意，这是一个构建环境—您必须构建库。

以下是我对XMPP解决方案对电池寿命的影响进行的计算:

The Android client must maintain a persistent TCP connection by waking up periodically to send a heartbeat to the XMPP server. This clearly imposes a cost in terms of power usage. An estimate of this cost is provided below: Using a 1400mAh battery (as supplied in the Nexus One and HTC Desire) An idle device, connected to an 3G network, uses approximately 5mA The wake-up, heartbeat, sleep cycle occurs every 5 minutes, takes three seconds to complete and uses 300mA The cost in battery usage per hour is therefore: 36 seconds 300mA = 3mAh sending heartbeat 3600 seconds 5mA = 5mAh at idle 4:95 + 3 = 7:95mAh combined A 1400mAh battery lasts approximately 11.6 days at idle and 7.3 days when running the application, which represents an approximate 37% reduction in battery life. However, a reduction in battery life of 37% represents the absolute worst case in practice given that devices are rarely completely idle.

谷歌正在贬低C2DM，但他们引入了GCM(谷歌云消息)，我认为他们没有任何配额，而且是免费的!不过它确实需要Android 2.2+ !http://developer.android.com/guide/google/gcm/index.html

GCM的问题是在这个过程中涉及到很多配置:

你必须在Android应用中添加大量样板文件 需要配置外部服务器与GCM服务器通信 您必须编写测试

如果你喜欢简单的东西(像我一样)，你应该试试UrbanAirship。这是(恕我直言)在应用程序中使用GCM的最简单方法，无需进行大量配置。它还提供了一个漂亮的GUI来测试是否正确地传递了GCM消息。

你可以在这里找到文档和入门指南 您可以在这里找到一个示例应用程序

注:我没有附属城市飞艇在任何方式

https://github.com/Guti/Google-Cloud-Messaging--Titanium-/blob/master/src/com/google/android/gcm/GCMRegistrar.java

它真的很好和工作的解决方案的推动。

请试一下

They have their listeners which has to be used by you by using their library classes in your code. You need not to bother about pushing. You have to send the message to server server will push the message to the device. They use OAuth. Regarding Protocols, there are two methods using CCS and XMPP. CCS just uses XMPP as an authenticated transport layer, so you can use most XMPP libraries to manage the connection. To send notifications to device you can write code in android app to send as well as your server code. the message sending will be done only by your code. Rest will be taken care by Google Server in GCM case. You can check detail at this link

http://developer.android.com/google/gcm/server.html

还有安全问题

谷歌云消息安全https://groups.google.com/forum/#!主题/ android-gcm / M-EevBitbhQ

In case your app is not running then also devices can recieve notification because you have to write code for broadcast listeners. In background it will be listening to server and whenever any message packet will be there it will recieve the message as notification. Android has service you need to not to bother about it. You have only to use those resources using the library class that makes your work easier and let them write if your app is not running then also it recieve notification. Obviously, there would be some listener whick make the app to recieve.Check "Recieve the message" section in this link

http://developer.android.com/google/gcm/client.html

它还将接受用户的请求。对于GCM，这就可以了。请勾选“发送信息”

http://developer.android.com/google/gcm/client.html

谷歌最近(2016年5月18日)宣布Firebase现在是移动开发者的统一平台，包括接近实时的推送通知。它也是多平台的:

该公司现在为所有Firebase用户提供免费和无限的服务 支持iOS、Android和Web的通知。

源