diff --git a/src/client/components/AppSelector.tsx b/src/client/components/AppSelector.tsx
new file mode 100644
index 0000000..19c8a82
--- /dev/null
+++ b/src/client/components/AppSelector.tsx
@@ -0,0 +1,76 @@
+import type { CSSProperties } from 'hono/jsx'
+import {
+  apps,
+  selectedApp,
+  setSelectedApp,
+  setSidebarSection,
+  sidebarSection,
+} from '../state'
+import {
+  AppItem,
+  AppList,
+  SectionSwitcher,
+  SectionTab,
+  StatusDot,
+} from '../styles'
+
+interface AppSelectorProps {
+  render: () => void
+  onSelect?: () => void
+  collapsed?: boolean
+  switcherStyle?: CSSProperties
+  listStyle?: CSSProperties
+}
+
+export function AppSelector({ render, onSelect, collapsed, switcherStyle, listStyle }: AppSelectorProps) {
+  const selectApp = (name: string) => {
+    setSelectedApp(name)
+    onSelect?.()
+    render()
+  }
+
+  const switchSection = (section: 'apps' | 'tools') => {
+    setSidebarSection(section)
+    render()
+  }
+
+  const regularApps = apps.filter(app => !app.tool)
+  const toolApps = apps.filter(app => app.tool)
+  const activeApps = sidebarSection === 'apps' ? regularApps : toolApps
+
+  return (
+    <>
+      {!collapsed && toolApps.length > 0 && (
+        <SectionSwitcher style={switcherStyle}>
+          <SectionTab active={sidebarSection === 'apps' ? true : undefined} onClick={() => switchSection('apps')}>
+            Apps
+          </SectionTab>
+          <SectionTab active={sidebarSection === 'tools' ? true : undefined} onClick={() => switchSection('tools')}>
+            Tools
+          </SectionTab>
+        </SectionSwitcher>
+      )}
+      <AppList style={listStyle}>
+        {activeApps.map(app => (
+          <AppItem
+            key={app.name}
+            onClick={() => selectApp(app.name)}
+            selected={app.name === selectedApp ? true : undefined}
+            style={collapsed ? { justifyContent: 'center', padding: '10px 12px' } : undefined}
+            title={collapsed ? app.name : undefined}
+          >
+            {collapsed ? (
+              <span style={{ fontSize: 18 }}>{app.icon}</span>
+            ) : (
+              <>
+                <span style={{ fontSize: 14 }}>{app.icon}</span>
+                {app.name}
+                <StatusDot state={app.state} style={{ marginLeft: 'auto' }} />
+              </>
+            )}
+          </AppItem>
+        ))}
+      </AppList>
+    </>
+  )
+}