1. WhatsApp 信使：
WhatsApp Messenger，或简称 WhatsApp，是 Facebook, Inc. 旗下的跨平台消息传递服务。它允许用户发送文本消息、语音消息、进行语音通话、视频通话、共享图像、文档、用户位置和其他媒体。
2. 脸书信使：
Facebook Messenger 是由 Facebook 开发的美国消息应用程序和平台。它允许用户发送消息、交换照片、视频、贴纸、音频和文件，对其他用户的消息做出反应并与机器人交互，支持语音和视频通话。
WhatsApp Messenger 和 Facebook Messenger 的区别：
| Facebook Messenger | |
|---|---|
| It is owned by Facebook, Inc. | It is also owned by Facebook, Inc. |
| It was launched on 3rd May, 2009. | It was launched on 9th Aug 2011. |
| Whatsapp does not require a username and password to log in | Facebook Messenger requires a Facebook login to get started. |
| Whatsapp allows to send up to 30 photos or videos at once. | There is no such limit in facebook messenger. |
| In whatsapp you can share your friend’s contact to your friends. | Facebook Messenger does not allow to share contacts. |
| In Whatsapp, there is an option to see when the person was last online. | In Facebook, Messenger you cannot see it. |
| You can set your status through whatsapp. | You can not set your status through Facebook Messenger. |
| Whatsapp allows to send documents using the app. | Facebook Messenger does not allow so. |
| You need a sim card to log in. | In Facebook Messenger you do not need a SIM card to log in. |
| Whatsapp messenger has end-to-end encryption. | Facebook Messenger does not have end-to-end encryption. |
| Whatsapp messenger does not have a facebook sign in option. | Facebook Messenger has a facebook sign in option. |