Demetrius Tautu

This plugin allows your visitors to subscribe to your push notifications as well as receive push notifications whenever you publish a new post.
The process of subscription is 100% automated and your subscribers will be saved within your DigitalPUSH account.
The process of sending notifications on a new post is also 100% automated and it will notify all your previously subscribed users with the following information: 
* Post title ( up to 64 characters ) 
* Post content without any HTML tags ( up to 128 characters ) 
* Post permalink 
* Post featured image ( If the post has no featured image, a standard bell image will be used instead. The same applies if your featured image is http:// instead of https:// )
The subscription is made by implementing the DigitalPUSH javascript library into your pages ( https://cdn.digitalpush.org/lib.js ), library which handles the entire process. 
The push notification sending process is handled by making a POST call from the plugin to the DigitalPUSH API ( https://api.digitalpush.org/push/ ).
To make use of the plugin you will need an account with DigitalPUSH which can be created here: https://digitalpush.org/register.php 
The registration is instant and completely free.
DigitalPUSH is a free to use push notifications service which can be found here: https://digitalpush.org 
DigitalPUSH terms of service: https://digitalpush.org/tos.php 
DigitalPUSH privacy policy: https://digitalpush.org/privacy.php

DigitalPUSH notifications

This plugin allows you to to implement push notifications with your WordPress blog.

Sjehutch

Browser Push Notifications By Passbeemedia – Send Push notifications to the browser We have built a one stop shop for sending push notifications to the browser .
Push Plugin Features:
<ul>
<li>Safari Web Push – Take advantage of web push (Desktop Push Notifications) on OS X Mavericks.</li>
<li>Detailed Analytics – Detailed Charts Built into your wordpress plugin</li>
<li>Send A Manual Post – Send Notifications to all your users manually </li>
<li>Schedule – Your Posts only get pushed when they are published </li>
</ul>
Its all FREE …

Passbeemedia Web Push Notification

Browser Push Notifications By Passbeemedia - Send Push notifications to the browser

DigitalPUSH notifications vs Passbeemedia Web Push Notification