diff --git a/app/helpers/notifications_helper.rb b/app/helpers/notifications_helper.rb
index fa55325cb..969a69e12 100644
--- a/app/helpers/notifications_helper.rb
+++ b/app/helpers/notifications_helper.rb
@@ -28,8 +28,8 @@ module NotificationsHelper
     tag.div id: dom_id(notification), class: "tray__item" do
       concat(
         link_to(notification,
-          class: [ "card card--notification", { "card--closed": notification.card.closed? } ],
-          data: { turbo_frame: "_top" },
+          class: [ "card card--notification", { "card--closed": notification.card.closed? }, { "unread": !notification.read? } ],
+          data: { turbo_frame: "_top", badge_target: "unread", action: "badge#update" },
           style: { "--card-color:": notification.card.color },
           &)
       )
@@ -42,7 +42,7 @@ module NotificationsHelper
           method: :delete,
           class: "card__notification-unread-indicator btn btn--circle borderless",
           title: "Mark as unread",
-          data: { action: "form#submit:stop", form_target: "submit" },
+          data: { action: "form#submit:stop badge#update:stop", form_target: "submit" },
           form: { data: { controller: "form" } } do
         concat(icon_tag("unseen"))
         concat(tag.span("Mark as unread", class: "for-screen-reader"))
@@ -51,7 +51,7 @@ module NotificationsHelper
       button_to read_notification_path(notification),
           class: "card__notification-unread-indicator btn btn--circle borderless",
           title: "Mark as read",
-          data: { action: "form#submit:stop", form_target: "submit" },
+          data: { action: "form#submit:stop badge#update:stop", form_target: "submit" },
           form: { data: { controller: "form" } } do
         concat(icon_tag("remove-med"))
         concat(tag.span("Mark as read", class: "for-screen-reader"))
diff --git a/app/javascript/controllers/badge_controller.js b/app/javascript/controllers/badge_controller.js
new file mode 100644
index 000000000..e84ee3013
--- /dev/null
+++ b/app/javascript/controllers/badge_controller.js
@@ -0,0 +1,43 @@
+import { Controller } from "@hotwired/stimulus"
+import { onNextEventLoopTick } from "helpers/timing_helpers"
+
+export default class extends Controller {
+  static targets = [ "unread" ]
+  static classes = [ "unread" ]
+
+  connect() {
+    onNextEventLoopTick(() => this.update())
+  }
+
+  update() {
+    onNextEventLoopTick(() => {
+      if (this.#available) {
+        const unreadCount = this.#unreadCount
+
+        console.log(unreadCount, this.unreadTargets)
+
+        if (unreadCount > 0) {
+          navigator.setAppBadge(unreadCount)
+        } else {
+          navigator.clearAppBadge()
+        }
+      }
+    })
+  }
+
+  clear() {
+    onNextEventLoopTick(() => {
+      if (this.#available) {
+        navigator.clearAppBadge()
+      }
+    })
+  }
+
+  get #unreadCount() {
+    return this.unreadTargets.filter(unreadTarget => unreadTarget.classList.contains(this.unreadClass)).length
+  }
+
+  get #available() {
+    return "setAppBadge" in navigator
+  }
+}
diff --git a/app/views/notifications/_tray.html.erb b/app/views/notifications/_tray.html.erb
index f87ac6f23..23caa68ea 100644
--- a/app/views/notifications/_tray.html.erb
+++ b/app/views/notifications/_tray.html.erb
@@ -1,6 +1,6 @@
 <%= turbo_stream_from Current.user, :notifications %>
 
-<section class="tray tray--notifications" data-controller="dialog">
+<section class="tray tray--notifications" data-controller="dialog badge" data-badge-unread-class="unread" data-action="turbo:render#update">
   <dialog class="tray__dialog"
       data-dialog-modal-value="false" data-dialog-target="dialog"
       data-action="keydown.esc->dialog#close:stop click@document->dialog#closeOnClickOutside">
@@ -10,7 +10,7 @@
       <%= link_to settings_notifications_path,
             class: "btn borderless tray__notification-settings",
             title: "Notification settings",
-            data: { action: "click->dialog#close" } do %>
+            data: { action: "dialog#close" } do %>
         <%= icon_tag "settings" %>
         <span class="translucent">Settings</span>
       <% end %>
@@ -28,7 +28,7 @@
       <%= button_to read_all_notifications_path,
             class: "btn borderless tray__clear-notifications",
             title: "Mark all notifications as read",
-            data: { action: "click->dialog#close", turbo_frame: "notifications" } do %>
+            data: { action: "dialog#close badge#clear", turbo_frame: "notifications" } do %>
         <%= icon_tag "check" %>
         <span class="translucent">Clear all</span>
       <% end %>
diff --git a/app/views/notifications/index.html.erb b/app/views/notifications/index.html.erb
index 4ef4d7fe2..eb84721c1 100644
--- a/app/views/notifications/index.html.erb
+++ b/app/views/notifications/index.html.erb
@@ -17,29 +17,31 @@
   </nav>
 <% end %>
 
-<section class="notifications-list panel center borderless unpad flex flex-column gap-half">
-  <% if @unread.any? %>
-    <div class="flex align-center justify-space-between margin-block-start margin-block-end-half">
-      <h2 class="txt-medium txt-uppercase txt-alert">New for you</h2>
-      <%= button_to "Mark all as read", read_all_notifications_path, class: "btn txt-small", form: { data: { turbo: false } } %>
+<div data-controller="badge" data-badge-unread-class="unread">
+  <section class="notifications-list panel center borderless unpad flex flex-column gap-half">
+    <% if @unread.any? %>
+      <div class="flex align-center justify-space-between margin-block-start margin-block-end-half">
+        <h2 class="txt-medium txt-uppercase txt-alert">New for you</h2>
+        <%= button_to "Mark all as read", read_all_notifications_path, class: "btn txt-small", form: { data: { turbo: false } }, data: { action: "badge#clear" } %>
+      </div>
+    <% else %>
+      <div class="notifications-list__empty-message pad border-radius border translucent" style="--border-style: dashed; --border-color: var(--color-ink); --border-radius: 0.2em;">
+        <strong>Nothing new for you.</strong>
+      </div>
+    <% end %>
+
+    <div id="notifications_list" contents>
+      <%= render partial: "notifications/notification", collection: @unread, cached: true %>
     </div>
-  <% else %>
-    <div class="notifications-list__empty-message pad border-radius border translucent" style="--border-style: dashed; --border-color: var(--color-ink); --border-radius: 0.2em;">
-      <strong>Nothing new for you.</strong>
+  </section>
+
+  <section class="notifications-list notifications-list--read panel center borderless unpad flex flex-column gap-half margin-block-start">
+    <h2 class="txt-medium margin-block-start-double margin-block-end-half txt-uppercase translucent">Previously seen</h2>
+
+    <div id="notifications_list_read" contents>
+      <%= render partial: "notifications/notification", collection: @page.records, cached: true %>
     </div>
-  <% end %>
-
-  <div id="notifications_list" contents>
-    <%= render partial: "notifications/notification", collection: @unread, cached: true %>
-  </div>
-</section>
-
-<section class="notifications-list notifications-list--read panel center borderless unpad flex flex-column gap-half margin-block-start">
-  <h2 class="txt-medium margin-block-start-double margin-block-end-half txt-uppercase translucent">Previously seen</h2>
-
-  <div id="notifications_list_read" contents>
-    <%= render partial: "notifications/notification", collection: @page.records, cached: true %>
-  </div>
-</section>
+  </section>
+</div>
 
 <%= notifications_next_page_link(@page) if @page.records.any? %>