diff --git a/muxplex/frontend/app.js b/muxplex/frontend/app.js
index 4cad1de..a10db36 100644
--- a/muxplex/frontend/app.js
+++ b/muxplex/frontend/app.js
@@ -1622,6 +1622,81 @@ function closeFlyoutMenu() {
   _flyoutRemoteId = null;
 }
 
+/**
+ * Open a bottom action sheet for the flyout menu (mobile).
+ * Same actions as the desktop flyout, but renders as a full-width bottom sheet.
+ */
+function _openFlyoutSheet() {
+  var viewType = _activeView;
+  if (viewType !== 'all' && viewType !== 'hidden') viewType = 'user';
+
+  var items = FLYOUT_MENU_MAP[viewType] || FLYOUT_MENU_MAP['all'];
+
+  var html = '<div class="flyout-sheet__backdrop"></div>';
+  html += '<div class="flyout-sheet__panel">';
+  html += '<div class="flyout-sheet__handle" aria-hidden="true"></div>';
+
+  for (var i = 0; i < items.length; i++) {
+    var item = items[i];
+    if (item.separator) {
+      html += '<div class="flyout-sheet__separator"></div>';
+      continue;
+    }
+
+    var label = item.label;
+    if (label.indexOf('{viewName}') !== -1) {
+      var displayName = _activeView;
+      if (displayName.length > 20) displayName = displayName.substring(0, 20) + '\u2026';
+      label = label.replace('{viewName}', escapeHtml(displayName));
+    }
+
+    var cls = 'flyout-sheet__item';
+    if (item.className && item.className.indexOf('danger') !== -1) cls += ' flyout-sheet__item--danger';
+
+    html += '<button class="' + cls + '" data-action="' + item.action + '">';
+    html += label;
+    html += '</button>';
+  }
+
+  html += '</div>';
+
+  var sheet = document.createElement('div');
+  sheet.className = 'flyout-sheet';
+  sheet.setAttribute('role', 'dialog');
+  sheet.setAttribute('aria-modal', 'true');
+  sheet.innerHTML = html;
+  document.body.appendChild(sheet);
+
+  // Backdrop closes
+  var backdrop = sheet.querySelector('.flyout-sheet__backdrop');
+  if (backdrop) {
+    backdrop.addEventListener('click', closeFlyoutMenu);
+  }
+
+  // Delegated action handler
+  var panel = sheet.querySelector('.flyout-sheet__panel');
+  if (panel) {
+    panel.addEventListener('click', function(e) {
+      var btn = e.target.closest('[data-action]');
+      if (!btn) return;
+
+      var action = btn.dataset.action;
+      if (action === 'add-to-view' || action === 'unhide-add-to-view') {
+        // On mobile, close sheet and open Add Sessions panel
+        closeFlyoutMenu();
+        openAddSessionsPanel();
+      } else if (action === 'kill') {
+        // Simple confirm on mobile (inline doesn't work well in sheets)
+        closeFlyoutMenu();
+        killSession(_flyoutSessionName, _flyoutRemoteId);
+      } else {
+        // Dispatch directly
+        _handleFlyoutClick(e);
+      }
+    });
+  }
+}
+
 /**
  * Click-outside handler for the flyout menu.
  * @param {MouseEvent} e
diff --git a/muxplex/tests/test_frontend_js.py b/muxplex/tests/test_frontend_js.py
index f5dedbd..51fdb28 100644
--- a/muxplex/tests/test_frontend_js.py
+++ b/muxplex/tests/test_frontend_js.py
@@ -3924,3 +3924,21 @@ def test_add_sessions_shows_device_name() -> None:
     assert "deviceName" in fn_body or "device" in fn_body, (
         "renderAddSessionsList must show device name for disambiguation"
     )
+
+
+# ─── Task 10: Mobile variants ────────────────────────────────────────────────
+
+
+def test_open_flyout_sheet_function_exists() -> None:
+    """app.js must define a _openFlyoutSheet function for mobile."""
+    assert "function _openFlyoutSheet" in _JS, (
+        "app.js must contain a _openFlyoutSheet function for mobile bottom sheet"
+    )
+
+
+def test_open_flyout_menu_checks_mobile() -> None:
+    """openFlyoutMenu must check isMobile() to decide between flyout and sheet."""
+    fn_body = _JS.split("function openFlyoutMenu")[1].split("\nfunction ")[0]
+    assert "isMobile" in fn_body, (
+        "openFlyoutMenu must check isMobile() to branch between flyout and sheet"
+    )