WhoKnew Signal™ Guide: WordPress Push Notifications in 5 Minutes

Every other WordPress push notification setup guide starts the same way: go to the vendor’s website, create an account, choose a pricing plan, copy an API key, then come back to WordPress and paste it in. That’s three steps and two browser tabs before you’ve done anything inside WordPress itself.

WhoKnew Signal™ works differently. It generates everything it needs — the VAPID cryptographic keys that identify your server to browsers, the service worker that receives push events, the web app manifest that enables iOS install — automatically on activation. There’s no external account because there is no external service. Everything runs from your WordPress server. Your subscriber data stays in your WordPress database. Your notifications travel directly from your server to your visitors’ browsers.

This guide covers the complete setup from install to first notification. For most WordPress sites, the process takes under ten minutes. For sites that want iOS push enabled, add another ten minutes for the PWA configuration and install shortcode placement.

Step 1: Install WhoKnew Signal™

Download WhoKnew Signal™ free from WordPress.org and install it through your WordPress dashboard: go to Plugins → Add New → Upload Plugin, select the downloaded zip file, and click Install Now. Alternatively, search “WhoKnew Signal” directly in the plugin search — the free version is available in the public directory.

Click Activate after installation completes. On activation, the plugin generates a VAPID key pair — a public and private cryptographic key unique to your WordPress installation. These keys are what identify your server as the authorized sender of push notifications to your subscribers’ browsers. They’re stored only in your WordPress database. No part of the key generation contacts any external server.

Step 2: Configure Your Notification Popup

Go to WhoKnew → Signal Push in your WordPress admin menu. The first tab you’ll see is the Popup tab — this controls the permission prompt your visitors see when you ask them to subscribe.

The default configuration shows a native browser permission prompt. This is the most honest implementation — it’s the standard browser dialog that users recognize and trust, and it requires no custom design work. If you want to add a soft-ask step before the native prompt — a custom dialog that explains what you’ll send before asking for browser permission — the Popup settings allow you to configure that. A soft-ask before the native prompt typically improves opt-in rates because visitors understand what they’re subscribing to before committing.

Set your notification icon — this appears in the notification itself on every browser and on the lock screen on mobile. Use a square image of at least 192×192 pixels, ideally 512×512. Your site logo works well. If you don’t set one, browsers use a generic icon.

Set up your welcome notification in the Welcome tab. This fires automatically when a new visitor subscribes — it’s typically the first push notification they receive from your site, and it confirms the subscription worked. Keep it short: your site name, a brief note on what they’ll receive, and optionally a link to your most popular content. A welcome notification arriving immediately after subscription dramatically increases the chance that the subscriber opens the next notification they receive from you.

Step 3: Configure the Web App Tab (Required for iOS)

Click the Web App tab in the Signal settings. This tab controls your site’s PWA manifest — the file that tells browsers how your site should appear and behave when installed to a phone’s home screen. Completing this step is required for iOS push notifications. It also improves the experience for Android users who install your site to their home screen.

Fill in the following fields:

• App Name — appears under the icon on the home screen. Use your site name or a short, recognizable version of it.
• Short Name — appears where space is limited. Keep it under 12 characters.
• App Icon — upload a square PNG at least 512×512 pixels. This becomes the home screen icon for visitors who install your site as a PWA. Signal automatically generates the required icon sizes from this upload.
• Theme Color — the color of the browser chrome and status bar when your site opens in standalone mode. Use your brand’s primary color.
• Display Mode — set to Standalone. This makes the PWA open without a browser address bar, giving it a native app feel.
• Offline Page — Signal can serve a custom offline page when visitors open your PWA without an internet connection. This is included free and prevents visitors from seeing a generic browser error if they’re offline.

Save the Web App settings. Signal generates and serves your manifest.json automatically — there’s no file to upload or edit manually. If you previously used Super PWA or PWA for WP for your manifest, you can deactivate those plugins now. Signal’s built-in Web App tab handles everything they do for this use case.

Step 4: Add Install Buttons for iPhone Visitors

Android visitors can receive push notifications after granting browser permission — no home screen install required. iPhone visitors require one additional step: they must add your site to their home screen as a PWA before they can grant push permission. This is an Apple platform requirement that applies regardless of which push plugin you use.

WhoKnew Signal includes a free shortcode — [wkspn_install_buttons] — that handles the entire install experience. Paste it on any page where you want visitors to be able to install your site. The shortcode automatically detects the visitor’s device and shows the appropriate experience:

• Android visitors — a one-tap “Add to Home Screen” button when the browser supports the Web App Install API; a manual instruction when it doesn’t
• iPhone visitors — a guided walkthrough modal that shows the exact steps: tap Share → scroll to Add to Home Screen → tap Add. The modal includes visual indicators that match what visitors see in Safari
• Chrome on iOS visitors — a note explaining that they need to complete the install in Safari, with a copy-URL button for convenience
• Already-installed visitors — the shortcode detects if the PWA is already installed and shows a confirmation message instead of the install prompt
• Desktop visitors — configurable behavior: you can show an install button, a message, or nothing at all

A good placement for the install shortcode is your homepage (in a sticky header or footer bar), a dedicated “Get Notifications” page you link to from your navigation, or inline in your most popular posts. The shortcode accepts style attributes to match your site’s visual design — see the Signal settings for preset options.

Step 5: Configure Auto-Send on Publish

Go to the General or Auto-Send tab in Signal settings. Enable auto-send on publish and review the post types listed. Signal automatically discovers every public post type registered on your WordPress installation — standard Posts, Pages, WooCommerce Products, The Events Calendar events, LearnDash courses, and any custom post types your theme or plugins register. Check the post types you want to trigger automatic push notifications when new content is published. Uncheck any types you want to control manually — draft-mode products, internal pages, or anything else that shouldn’t automatically notify subscribers.

This auto-discovery feature is worth noting specifically because most push notification plugins require you to enter post type slugs manually — and if you add a new plugin that registers a custom post type later, you have to go back and add it. Signal finds new post types automatically without any action on your part.

Step 6: Send Your First Test Notification

Before sending to subscribers, test the full flow on your own device. Visit your WordPress site in a browser that supports web push — Chrome, Firefox, or Edge on desktop; Safari on macOS 13+; Chrome or Safari on Android; Safari on iPhone (after completing the PWA install). When the permission prompt appears, allow notifications. Go to WhoKnew → Signal Push → Campaigns in your WordPress admin, create a new campaign with a test title and message, and send it to yourself.

The notification should appear within a few seconds — on your desktop as a browser notification, on Android as a lock screen notification or banner, on iPhone as a notification from the installed PWA. If you’re on iOS and haven’t completed the Add to Home Screen step yet, do that first: open your site in Safari, tap Share, tap Add to Home Screen, tap Add, then open the site from the home screen icon before allowing notifications.

What the Pro Version Adds

The free version of WhoKnew Signal includes everything described in this guide — unlimited subscribers, all core push features, PWA manifest, iOS support, install shortcode, auto-send on publish, welcome notification, VAPID backup/restore, and click tracking. The free tier is fully functional for most blogs, publishers, and smaller WordPress sites that want self-hosted push without any SaaS fees.

WhoKnew Signal Pro at $8/month or $80/year adds the features needed for growth-stage sites and WooCommerce stores:

• WooCommerce push triggers — abandoned cart recovery, back-in-stock alerts, price drop notifications, new product broadcasts, and order status push to linked WordPress accounts
• Advanced analytics — per-campaign click-through rate tracking, daily click charts, browser and platform breakdowns, subscriber growth trends
• Smart segments — target notifications by engagement level, device type, subscription tenure, or WooCommerce purchase behavior
• A/B campaign testing — split-test notification titles and bodies with automatic winner selection
• Scheduled campaigns — send at a specific time rather than immediately
• Action buttons — add a clickable secondary button to notifications
• Rich images — large image in the notification body
• UTM tagging — automatic utm_source=push on all campaign links
• Background batched sending — performance profiles optimized for shared hosting, VPS, and cloud environments
• Subscriber import/export — full list portability for server migrations
• SMS notifications (optional) — send text messages to opted-in subscribers using your own Twilio account; no markup, no per-message SaaS fee, ~$1/mo for a Twilio number

VAPID Key Backup — Do This Before You Change Hosting

One step most setup guides skip: before you change hosting providers, migrate to a new server, or create a staging clone, export your VAPID keys from Signal settings. Your VAPID keys are the cryptographic identity that your subscribers’ browsers use to verify your notifications. If you regenerate them on a new server, every existing subscriber will need to re-opt-in — their browser will reject notifications signed with a different key pair.

Go to WhoKnew → Signal Push → Settings → VAPID and use the backup/restore function. Export the key pair as a JSON file and keep it in a safe location. When you set up Signal on a new server, restore this file before you send any notifications. Your existing subscribers will continue receiving notifications without any re-permission required.

Who knew that setting up push notifications on WordPress didn’t require creating an account at a third-party service, copying an API key, or trusting your subscriber list to anyone other than yourself.