diff --git a/src/Command/SeedFakeDevicesCommand.php b/src/Command/SeedFakeDevicesCommand.php
new file mode 100644
index 0000000..29bc993
--- /dev/null
+++ b/src/Command/SeedFakeDevicesCommand.php
@@ -0,0 +1,123 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Command;
+
+use App\Entity\Device;
+use App\Entity\User;
+use App\Enum\DeviceModel;
+use App\Enum\Orientation;
+use Doctrine\ORM\EntityManagerInterface;
+use Symfony\Component\Console\Attribute\AsCommand;
+use Symfony\Component\Console\Command\Command;
+use Symfony\Component\Console\Input\InputArgument;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Input\InputOption;
+use Symfony\Component\Console\Output\OutputInterface;
+use Symfony\Component\Console\Style\SymfonyStyle;
+
+/**
+ * Seeds fake devices on a user account so the multi-frame UI can be
+ * exercised without provisioning real hardware. Each fake gets a MAC in
+ * the AA:BB:CC:DD:EE:** range so the command can clean them up on re-run
+ * without touching real devices.
+ *
+ *   docker exec pictureframe-php-1 php bin/console app:seed-fake-devices user@example.com
+ *   docker exec pictureframe-php-1 php bin/console app:seed-fake-devices user@example.com --remove
+ */
+#[AsCommand(
+    name: 'app:seed-fake-devices',
+    description: 'Seed fake devices on a user account for UI testing',
+)]
+final class SeedFakeDevicesCommand extends Command
+{
+    private const FAKE_MAC_PREFIX = 'AA:BB:CC:DD:EE:';
+
+    public function __construct(
+        private readonly EntityManagerInterface $em,
+    ) {
+        parent::__construct();
+    }
+
+    protected function configure(): void
+    {
+        $this
+            ->addArgument('email', InputArgument::REQUIRED, 'Account email')
+            ->addOption('remove', null, InputOption::VALUE_NONE, 'Remove previously-seeded fake devices and exit');
+    }
+
+    protected function execute(InputInterface $input, OutputInterface $output): int
+    {
+        $io    = new SymfonyStyle($input, $output);
+        $email = (string) $input->getArgument('email');
+
+        $user = $this->em->getRepository(User::class)->findOneBy(['email' => $email]);
+        if ($user === null) {
+            $io->error("No user found with email '$email'.");
+            return Command::FAILURE;
+        }
+
+        // Always sweep prior fakes first (re-runs stay idempotent).
+        $existing = $this->em->getRepository(Device::class)->createQueryBuilder('d')
+            ->where('d.user = :u AND d.mac LIKE :prefix')
+            ->setParameter('u', $user)
+            ->setParameter('prefix', self::FAKE_MAC_PREFIX . '%')
+            ->getQuery()
+            ->getResult();
+        foreach ($existing as $d) {
+            $this->em->remove($d);
+        }
+        if ($existing) {
+            $this->em->flush();
+            $io->writeln(sprintf('Removed %d existing fake device(s).', count($existing)));
+        }
+
+        if ($input->getOption('remove')) {
+            $io->success('Done.');
+            return Command::SUCCESS;
+        }
+
+        // Five fakes covering each status state.
+        $now   = new \DateTimeImmutable();
+        $fakes = [
+            ['name' => 'Living Room', 'orientation' => Orientation::Landscape, 'lastSeen' => 'PT5M',  'wakeHour' => null],
+            ['name' => 'Kitchen',     'orientation' => Orientation::Landscape, 'lastSeen' => 'PT90M', 'wakeHour' => null],
+            ['name' => 'Bedroom',     'orientation' => Orientation::Portrait,  'lastSeen' => 'P3D',   'wakeHour' => null],
+            ['name' => "Mom's Place", 'orientation' => Orientation::Portrait,  'lastSeen' => null,    'wakeHour' => null],
+            ['name' => 'Cabin',       'orientation' => Orientation::Landscape, 'lastSeen' => 'PT1H',  'wakeHour' => 4],
+        ];
+
+        $reflLastSeen = new \ReflectionProperty(Device::class, 'lastSeenAt');
+        $reflLastSeen->setAccessible(true);
+
+        foreach ($fakes as $i => $cfg) {
+            $device = new Device();
+            $device->setMac(sprintf(self::FAKE_MAC_PREFIX . '%02X', $i + 1));
+            $device->setName($cfg['name']);
+            $device->setModel(DeviceModel::V1);
+            $device->setOrientation($cfg['orientation']);
+            $device->setRotationIntervalMinutes(60);
+            $device->setTimezone('America/New_York');
+            $device->setUser($user);
+            if ($cfg['wakeHour'] !== null) {
+                $device->setWakeHour($cfg['wakeHour']);
+            }
+            if ($cfg['lastSeen'] !== null) {
+                $reflLastSeen->setValue($device, $now->sub(new \DateInterval($cfg['lastSeen'])));
+            }
+            $this->em->persist($device);
+
+            $io->writeln(sprintf(
+                '  + %s — %s, %s',
+                $cfg['name'],
+                $cfg['orientation']->value,
+                $cfg['lastSeen'] === null ? 'never seen' : 'last seen ' . $cfg['lastSeen'] . ' ago',
+            ));
+        }
+
+        $this->em->flush();
+        $io->success(sprintf('Seeded %d fake devices for %s.', count($fakes), $email));
+        return Command::SUCCESS;
+    }
+}