Push technology refers to sending direct messages or notifications to pushbutton clients (i.e. mobile devices) from a centralized broadcasting server (messages).
While pull technology requires the client to provide certain data from the server responds by sending data to the device. You can get a lot of information regarding the app notification analytics via Notifyme.
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For example push messages can be sent in several ways. The most commonly used sending technology is Short Message Service (SMS), which is used to send text messages from one mobile device to another.
Then there is the Multimedia Messaging Service (MMS), which uses SMS and Wireless Application Protocol (WAP) to deliver multimedia messages.
MMS is mainly used to send photos and videos from one mobile device to another, this tool actually allows you to send messages that can activate applications or signals on the mobile device.
Push notifications allow distinct apps to notify you of new messages or events without actually opening the app. This is similar to the way a text message makes a sound and appears on the screen.
Whenever an event occurs that causes the app to send a notification, the notification is sent to the user via one of three options: sound, screen alert, or badge.
Most apps that support push notifications allow users to choose which of the three notifications (if any) they want to use to notify them of updates.