A push notification is a brief and attention-grabbing message that brands can send to their customers even when they are not currently engaging with the app or the website. These messages come from the apps you have installed on your phone.
Modern push notifications were popularized by Apple that in 2009 launched push notification support for iOS and the Apple Push Notification Service (APNs). Google introduced push notification support on Android in 2010.
Why are they so important?
Push notifications are the follow-up to user acquisition. They are great for boosting retention and engagement rates. If they are timely, personal, and actionable they have the potential to be the most intuitive and intimate way to interact with your users. Keep in mind that push notifications only reach users who have installed your app