SSL Certificates and Web Push Notifications
Web push notifications or Website push notifications work only via an HTTPS connection with the website. An HTTPS connection is possible only after a SSL certificate is installed for your website. Once the website loads via HTTPS, then web browser push notifications can be shown.
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Mobile & Desktop web push notifications are enabled by a SSL Certificate
For using website push notifications you need to setup your own web app such that you can launch notifications based on certain rules or conditions. Alternately, signup with a well-known service such as PushEngage and use their built-in push marketing tools.
Currently, web push notifications are supported on most modern web browsers. Once setup you can reach your audience on their browser at a time of your choosing and send interest-based & personalised communications.
Use of Web Push notifications is a prerequisite to creating a Progressive Web App (PWA). Hence, enabling HTTPS is a must to create a PWA.