diff --git a/pages/passkey-register-cross-device.vue b/pages/passkey-register-cross-device.vue
new file mode 100644
index 0000000..c4b4b36
--- /dev/null
+++ b/pages/passkey-register-cross-device.vue
@@ -0,0 +1,142 @@
+<template>
+  <div class="min-h-screen bg-gray-900 text-white flex items-center justify-center p-4">
+    <div class="max-w-md w-full bg-gray-800 rounded-lg p-6 space-y-4">
+      <h1 class="text-2xl font-bold text-center">Passkey-Registrierung</h1>
+      
+      <div v-if="status === 'loading'" class="text-center">
+        <div class="animate-spin rounded-full h-12 w-12 border-b-2 border-white mx-auto mb-4"></div>
+        <p>Lade Registrierungsoptionen...</p>
+      </div>
+      
+      <div v-else-if="status === 'waiting'" class="text-center">
+        <div class="animate-pulse text-4xl mb-4">🔐</div>
+        <p class="text-lg mb-2">Warte auf Passkey-Authentifizierung...</p>
+        <p class="text-sm text-gray-400">Bitte bestätigen Sie die Registrierung auf diesem Gerät.</p>
+      </div>
+      
+      <div v-else-if="status === 'error'" class="text-center text-red-400">
+        <p class="text-lg font-semibold mb-2">Fehler</p>
+        <p>{{ errorMessage }}</p>
+        <button 
+          @click="retry" 
+          class="mt-4 px-4 py-2 bg-primary-600 hover:bg-primary-700 rounded"
+        >
+          Erneut versuchen
+        </button>
+      </div>
+      
+      <div v-else-if="status === 'success'" class="text-center text-green-400">
+        <p class="text-lg font-semibold mb-2">✅ Erfolgreich!</p>
+        <p>Die Credential-Response wurde an den Desktop-Browser gesendet.</p>
+      </div>
+    </div>
+  </div>
+</template>
+
+<script setup>
+import { ref, onMounted } from 'vue'
+
+const status = ref('loading')
+const errorMessage = ref('')
+const registrationId = ref('')
+
+// Hole registrationId aus URL-Parameter
+onMounted(async () => {
+  const route = useRoute()
+  registrationId.value = route.query.registrationId || ''
+  
+  if (!registrationId.value) {
+    status.value = 'error'
+    errorMessage.value = 'Keine registrationId in der URL gefunden.'
+    return
+  }
+  
+  await startRegistration()
+})
+
+async function startRegistration() {
+  try {
+    status.value = 'loading'
+    
+    // Hole Options vom Server
+    console.log('[DEBUG] Fetching options for registrationId:', registrationId.value)
+    const optionsResponse = await fetch(`/api/auth/register-passkey-options/${registrationId.value}`, {
+      method: 'GET',
+      headers: {
+        'Content-Type': 'application/json'
+      }
+    })
+    
+    if (!optionsResponse.ok) {
+      throw new Error(`Options request failed: ${optionsResponse.status}`)
+    }
+    
+    const optionsData = await optionsResponse.json()
+    
+    if (!optionsData.success || !optionsData.options) {
+      throw new Error('Invalid options response')
+    }
+    
+    console.log('[DEBUG] Options received:', {
+      hasChallenge: !!optionsData.options.challenge,
+      rpId: optionsData.options.rp?.id,
+      timeout: optionsData.options.timeout
+    })
+    
+    // Importiere @simplewebauthn/browser
+    const mod = await import('@simplewebauthn/browser')
+    
+    if (!mod.startRegistration) {
+      throw new Error('startRegistration ist nicht verfügbar')
+    }
+    
+    status.value = 'waiting'
+    
+    console.log('[DEBUG] Calling startRegistration on smartphone...')
+    
+    // Rufe startRegistration auf
+    const credential = await mod.startRegistration({ optionsJSON: optionsData.options })
+    
+    console.log('[DEBUG] Credential received:', {
+      id: credential.id,
+      type: credential.type
+    })
+    
+    // Sende Credential-Response an den Server
+    const verifyResponse = await fetch('/api/auth/register-passkey', {
+      method: 'POST',
+      headers: {
+        'Content-Type': 'application/json'
+      },
+      body: JSON.stringify({
+        registrationId: registrationId.value,
+        credential
+      })
+    })
+    
+    if (!verifyResponse.ok) {
+      const errorData = await verifyResponse.json().catch(() => ({}))
+      throw new Error(errorData.message || `Verification failed: ${verifyResponse.status}`)
+    }
+    
+    const verifyData = await verifyResponse.json()
+    
+    if (verifyData.success) {
+      status.value = 'success'
+      console.log('[DEBUG] Registration successful!')
+    } else {
+      throw new Error(verifyData.message || 'Registrierung fehlgeschlagen')
+    }
+    
+  } catch (error) {
+    console.error('[DEBUG] Registration error:', error)
+    status.value = 'error'
+    errorMessage.value = error.message || 'Unbekannter Fehler'
+  }
+}
+
+function retry() {
+  status.value = 'loading'
+  startRegistration()
+}
+</script>
diff --git a/server/middleware/log-requests.js b/server/middleware/log-requests.js
index 7f453ee..3e54722 100644
--- a/server/middleware/log-requests.js
+++ b/server/middleware/log-requests.js
@@ -19,14 +19,16 @@ export default defineEventHandler((event) => {
     '/api/auth/passkeys/register',
     '/api/auth/passkeys/authentication-options',
     '/api/auth/passkeys/login',
-    '/api/auth/passkeys/recovery'
+    '/api/auth/passkeys/recovery',
+    '/passkey-register-cross-device'
   ]
   
-  const isPasskeyEndpoint = passkeyEndpoints.some(ep => path.startsWith(ep))
+  // Logge auch alle Requests vom Smartphone (Mobile User-Agent)
+  const isMobile = /Mobile|Android|iPhone|iPad/i.test(userAgent || '')
+  const isPasskeyEndpoint = passkeyEndpoints.some(ep => path.startsWith(ep)) || (isMobile && path.startsWith('/'))
   
   if (isPasskeyEndpoint) {
     const timestamp = new Date().toISOString()
-    const isMobile = /Mobile|Android|iPhone|iPad/i.test(userAgent || '')
     
     console.log('')
     console.log('─'.repeat(80))
@@ -51,6 +53,12 @@ export default defineEventHandler((event) => {
       console.log(`[REQUEST] ⚠️ Wenn dieser Request vom Smartphone kommt, sollte der User-Agent Mobile/Android/iPhone enthalten`)
     }
     
+    // Logge alle Requests vom Smartphone (für Debugging)
+    if (isMobile && path.startsWith('/') && !path.startsWith('/_nuxt') && !path.startsWith('/api')) {
+      console.log(`[REQUEST] 📱 SMARTPHONE REQUEST - ${path}`)
+      console.log(`[REQUEST] ⚠️ Wenn das Smartphone die Website öffnet, sollten hier Requests erscheinen`)
+    }
+    
     console.log('─'.repeat(80))
     console.log('')
   }