diff --git a/recipes/firebaselab/firebaselab.expected/empty_devices.json b/recipes/firebaselab/firebaselab.expected/empty_devices.json
new file mode 100644
index 0000000..30e03d9
--- /dev/null
+++ b/recipes/firebaselab/firebaselab.expected/empty_devices.json
@@ -0,0 +1,533 @@
+[
+  {
+    "cmd": [],
+    "name": "Checkout flutter/flutter"
+  },
+  {
+    "cmd": [
+      "python3",
+      "-u",
+      "RECIPE_MODULE[depot_tools::git]/resources/git_setup.py",
+      "--path",
+      "[START_DIR]/flutter",
+      "--url",
+      "https://flutter.googlesource.com/mirrors/flutter"
+    ],
+    "name": "Checkout flutter/flutter.git setup",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "fetch",
+      "origin",
+      "master",
+      "--recurse-submodules",
+      "--progress",
+      "--tags"
+    ],
+    "cwd": "[START_DIR]/flutter",
+    "env": {
+      "PATH": "RECIPE_REPO[depot_tools]:<PATH>"
+    },
+    "infra_step": true,
+    "name": "Checkout flutter/flutter.git fetch",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "checkout",
+      "-f",
+      "FETCH_HEAD"
+    ],
+    "cwd": "[START_DIR]/flutter",
+    "infra_step": true,
+    "name": "Checkout flutter/flutter.git checkout",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "rev-parse",
+      "HEAD"
+    ],
+    "cwd": "[START_DIR]/flutter",
+    "infra_step": true,
+    "name": "Checkout flutter/flutter.read revision",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@",
+      "@@@STEP_TEXT@<br/>checked out 'deadbeef'<br/>@@@",
+      "@@@SET_BUILD_PROPERTY@got_revision@\"deadbeef\"@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "clean",
+      "-f",
+      "-d",
+      "-x"
+    ],
+    "cwd": "[START_DIR]/flutter",
+    "infra_step": true,
+    "name": "Checkout flutter/flutter.git clean",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "submodule",
+      "sync"
+    ],
+    "cwd": "[START_DIR]/flutter",
+    "infra_step": true,
+    "name": "Checkout flutter/flutter.submodule sync",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "submodule",
+      "update",
+      "--init",
+      "--recursive"
+    ],
+    "cwd": "[START_DIR]/flutter",
+    "infra_step": true,
+    "name": "Checkout flutter/flutter.submodule update",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "git",
+      "rev-parse",
+      "HEAD"
+    ],
+    "cwd": "[START_DIR]/flutter",
+    "infra_step": true,
+    "name": "git rev-parse"
+  },
+  {
+    "cmd": [
+      "flutter",
+      "doctor",
+      "-v"
+    ],
+    "cwd": "[START_DIR]/flutter",
+    "env": {
+      "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
+      "GIT_BRANCH": "",
+      "LUCI_BRANCH": "",
+      "LUCI_CI": "True",
+      "LUCI_PR": "",
+      "OS": "linux",
+      "PUB_CACHE": "[START_DIR]/.pub-cache",
+      "REVISION": "12345abcde12345abcde12345abcde12345abcde",
+      "SDK_CHECKOUT_PATH": "[START_DIR]/flutter"
+    },
+    "env_prefixes": {
+      "PATH": [
+        "[START_DIR]/flutter/bin",
+        "[START_DIR]/flutter/bin/cache/dart-sdk/bin"
+      ]
+    },
+    "name": "flutter doctor"
+  },
+  {
+    "cmd": [
+      "flutter",
+      "update-packages",
+      "-v"
+    ],
+    "cwd": "[START_DIR]/flutter",
+    "env": {
+      "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
+      "GIT_BRANCH": "",
+      "LUCI_BRANCH": "",
+      "LUCI_CI": "True",
+      "LUCI_PR": "",
+      "OS": "linux",
+      "PUB_CACHE": "[START_DIR]/.pub-cache",
+      "REVISION": "12345abcde12345abcde12345abcde12345abcde",
+      "SDK_CHECKOUT_PATH": "[START_DIR]/flutter"
+    },
+    "env_prefixes": {
+      "PATH": [
+        "[START_DIR]/flutter/bin",
+        "[START_DIR]/flutter/bin/cache/dart-sdk/bin"
+      ]
+    },
+    "infra_step": true,
+    "name": "download dependencies"
+  },
+  {
+    "cmd": [],
+    "name": "test_execution",
+    "~followup_annotations": [
+      "@@@STEP_LOG_LINE@logcat@@@@",
+      "@@@STEP_LOG_END@logcat@@@"
+    ]
+  },
+  {
+    "cmd": [],
+    "name": "test_execution.ensure gcloud",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "vpython3",
+      "-u",
+      "RECIPE_MODULE[recipe_engine::file]/resources/fileutil.py",
+      "--json-output",
+      "/path/to/tmp/json",
+      "copy",
+      "RECIPE_MODULE[fuchsia::gcloud]/resources/tool_manifest.json",
+      "/path/to/tmp/json"
+    ],
+    "cwd": "[START_DIR]/flutter/dev/integration_tests/the_task",
+    "env": {
+      "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
+      "GIT_BRANCH": "",
+      "LUCI_BRANCH": "",
+      "LUCI_CI": "True",
+      "LUCI_PR": "",
+      "OS": "linux",
+      "PUB_CACHE": "[START_DIR]/.pub-cache",
+      "REVISION": "12345abcde12345abcde12345abcde12345abcde",
+      "SDK_CHECKOUT_PATH": "[START_DIR]/flutter"
+    },
+    "env_prefixes": {
+      "PATH": [
+        "[START_DIR]/flutter/bin",
+        "[START_DIR]/flutter/bin/cache/dart-sdk/bin"
+      ]
+    },
+    "infra_step": true,
+    "name": "test_execution.ensure gcloud.read manifest",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@2@@@",
+      "@@@STEP_LOG_LINE@tool_manifest.json@{@@@",
+      "@@@STEP_LOG_LINE@tool_manifest.json@  \"path\": \"path/to/gcloud\",@@@",
+      "@@@STEP_LOG_LINE@tool_manifest.json@  \"version\": \"version:pinned-version\"@@@",
+      "@@@STEP_LOG_LINE@tool_manifest.json@}@@@",
+      "@@@STEP_LOG_END@tool_manifest.json@@@"
+    ]
+  },
+  {
+    "cmd": [],
+    "name": "test_execution.ensure gcloud.install path/to/gcloud",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@2@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "vpython3",
+      "-u",
+      "RECIPE_MODULE[recipe_engine::file]/resources/fileutil.py",
+      "--json-output",
+      "/path/to/tmp/json",
+      "ensure-directory",
+      "--mode",
+      "0777",
+      "[START_DIR]/cipd_tool/path/to/gcloud/version%3Apinned-version"
+    ],
+    "cwd": "[START_DIR]/flutter/dev/integration_tests/the_task",
+    "env": {
+      "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
+      "GIT_BRANCH": "",
+      "LUCI_BRANCH": "",
+      "LUCI_CI": "True",
+      "LUCI_PR": "",
+      "OS": "linux",
+      "PUB_CACHE": "[START_DIR]/.pub-cache",
+      "REVISION": "12345abcde12345abcde12345abcde12345abcde",
+      "SDK_CHECKOUT_PATH": "[START_DIR]/flutter"
+    },
+    "env_prefixes": {
+      "PATH": [
+        "[START_DIR]/flutter/bin",
+        "[START_DIR]/flutter/bin/cache/dart-sdk/bin"
+      ]
+    },
+    "infra_step": true,
+    "name": "test_execution.ensure gcloud.install path/to/gcloud.ensure package directory",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@3@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "cipd",
+      "ensure",
+      "-root",
+      "[START_DIR]/cipd_tool/path/to/gcloud/version%3Apinned-version",
+      "-ensure-file",
+      "path/to/gcloud version:pinned-version",
+      "-max-threads",
+      "0",
+      "-json-output",
+      "/path/to/tmp/json"
+    ],
+    "cwd": "[START_DIR]/flutter/dev/integration_tests/the_task",
+    "env": {
+      "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
+      "GIT_BRANCH": "",
+      "LUCI_BRANCH": "",
+      "LUCI_CI": "True",
+      "LUCI_PR": "",
+      "OS": "linux",
+      "PUB_CACHE": "[START_DIR]/.pub-cache",
+      "REVISION": "12345abcde12345abcde12345abcde12345abcde",
+      "SDK_CHECKOUT_PATH": "[START_DIR]/flutter"
+    },
+    "env_prefixes": {
+      "PATH": [
+        "[START_DIR]/flutter/bin",
+        "[START_DIR]/flutter/bin/cache/dart-sdk/bin"
+      ]
+    },
+    "infra_step": true,
+    "name": "test_execution.ensure gcloud.install path/to/gcloud.ensure_installed",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@3@@@",
+      "@@@STEP_LOG_LINE@json.output@{@@@",
+      "@@@STEP_LOG_LINE@json.output@  \"result\": {@@@",
+      "@@@STEP_LOG_LINE@json.output@    \"\": [@@@",
+      "@@@STEP_LOG_LINE@json.output@      {@@@",
+      "@@@STEP_LOG_LINE@json.output@        \"instance_id\": \"resolved-instance_id-of-version:pinned-v\", @@@",
+      "@@@STEP_LOG_LINE@json.output@        \"package\": \"path/to/gcloud\"@@@",
+      "@@@STEP_LOG_LINE@json.output@      }@@@",
+      "@@@STEP_LOG_LINE@json.output@    ]@@@",
+      "@@@STEP_LOG_LINE@json.output@  }@@@",
+      "@@@STEP_LOG_LINE@json.output@}@@@",
+      "@@@STEP_LOG_END@json.output@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "[START_DIR]/cipd_tool/path/to/gcloud/version%3Apinned-version/bin/gcloud",
+      "--quiet",
+      "config",
+      "set",
+      "project",
+      "flutter-infra-staging"
+    ],
+    "cwd": "[START_DIR]/flutter/dev/integration_tests/the_task",
+    "env": {
+      "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
+      "GIT_BRANCH": "",
+      "LUCI_BRANCH": "",
+      "LUCI_CI": "True",
+      "LUCI_PR": "",
+      "OS": "linux",
+      "PUB_CACHE": "[START_DIR]/.pub-cache",
+      "REVISION": "12345abcde12345abcde12345abcde12345abcde",
+      "SDK_CHECKOUT_PATH": "[START_DIR]/flutter"
+    },
+    "env_prefixes": {
+      "PATH": [
+        "[START_DIR]/flutter/bin",
+        "[START_DIR]/flutter/bin/cache/dart-sdk/bin"
+      ]
+    },
+    "infra_step": true,
+    "name": "test_execution.gcloud --quiet",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "flutter",
+      "build",
+      "appbundle",
+      "--target-platform",
+      "android-arm,android-arm64"
+    ],
+    "cwd": "[START_DIR]/flutter/dev/integration_tests/the_task",
+    "env": {
+      "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
+      "GIT_BRANCH": "",
+      "LUCI_BRANCH": "",
+      "LUCI_CI": "True",
+      "LUCI_PR": "",
+      "OS": "linux",
+      "PUB_CACHE": "[START_DIR]/.pub-cache",
+      "REVISION": "12345abcde12345abcde12345abcde12345abcde",
+      "SDK_CHECKOUT_PATH": "[START_DIR]/flutter"
+    },
+    "env_prefixes": {
+      "PATH": [
+        "[START_DIR]/flutter/bin",
+        "[START_DIR]/flutter/bin/cache/dart-sdk/bin"
+      ]
+    },
+    "name": "test_execution.Build appbundle",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "[START_DIR]/cipd_tool/path/to/gcloud/version%3Apinned-version/bin/gcloud",
+      "firebase",
+      "test",
+      "android",
+      "run",
+      "--type",
+      "robo",
+      "--app",
+      "build/app/outputs/bundle/release/app-release.aab",
+      "--timeout",
+      "2m",
+      "--results-bucket=gs://flutter_firebase_testlab_staging",
+      "--results-dir=the_task/fake-task-id",
+      "--device",
+      "model=redfin,version=30",
+      "--device",
+      "model=griffin,version=24"
+    ],
+    "cwd": "[START_DIR]/flutter/dev/integration_tests/the_task",
+    "env": {
+      "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
+      "GIT_BRANCH": "",
+      "LUCI_BRANCH": "",
+      "LUCI_CI": "True",
+      "LUCI_PR": "",
+      "OS": "linux",
+      "PUB_CACHE": "[START_DIR]/.pub-cache",
+      "REVISION": "12345abcde12345abcde12345abcde12345abcde",
+      "SDK_CHECKOUT_PATH": "[START_DIR]/flutter"
+    },
+    "env_prefixes": {
+      "PATH": [
+        "[START_DIR]/flutter/bin",
+        "[START_DIR]/flutter/bin/cache/dart-sdk/bin"
+      ]
+    },
+    "name": "test_execution.gcloud firebase",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "python3",
+      "-u",
+      "RECIPE_MODULE[depot_tools::gsutil]/resources/gsutil_smart_retry.py",
+      "--",
+      "RECIPE_REPO[depot_tools]/gsutil.py",
+      "----",
+      "cp",
+      "gs://flutter_firebase_testlab_staging/the_task/fake-task-id/*/logcat",
+      "[CLEANUP]"
+    ],
+    "cwd": "[START_DIR]/flutter/dev/integration_tests/the_task",
+    "env": {
+      "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
+      "GIT_BRANCH": "",
+      "LUCI_BRANCH": "",
+      "LUCI_CI": "True",
+      "LUCI_PR": "",
+      "OS": "linux",
+      "PUB_CACHE": "[START_DIR]/.pub-cache",
+      "REVISION": "12345abcde12345abcde12345abcde12345abcde",
+      "SDK_CHECKOUT_PATH": "[START_DIR]/flutter"
+    },
+    "env_prefixes": {
+      "PATH": [
+        "[START_DIR]/flutter/bin",
+        "[START_DIR]/flutter/bin/cache/dart-sdk/bin"
+      ]
+    },
+    "infra_step": true,
+    "name": "test_execution.gsutil download",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "vpython3",
+      "-u",
+      "RECIPE_MODULE[recipe_engine::file]/resources/fileutil.py",
+      "--json-output",
+      "/path/to/tmp/json",
+      "copy",
+      "[CLEANUP]/logcat",
+      "/path/to/tmp/"
+    ],
+    "cwd": "[START_DIR]/flutter/dev/integration_tests/the_task",
+    "env": {
+      "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
+      "GIT_BRANCH": "",
+      "LUCI_BRANCH": "",
+      "LUCI_CI": "True",
+      "LUCI_PR": "",
+      "OS": "linux",
+      "PUB_CACHE": "[START_DIR]/.pub-cache",
+      "REVISION": "12345abcde12345abcde12345abcde12345abcde",
+      "SDK_CHECKOUT_PATH": "[START_DIR]/flutter"
+    },
+    "env_prefixes": {
+      "PATH": [
+        "[START_DIR]/flutter/bin",
+        "[START_DIR]/flutter/bin/cache/dart-sdk/bin"
+      ]
+    },
+    "infra_step": true,
+    "name": "test_execution.read",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@",
+      "@@@STEP_LOG_END@logcat@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "grep",
+      "E/flutter",
+      "[CLEANUP]/logcat"
+    ],
+    "cwd": "[START_DIR]/flutter/dev/integration_tests/the_task",
+    "env": {
+      "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
+      "GIT_BRANCH": "",
+      "LUCI_BRANCH": "",
+      "LUCI_CI": "True",
+      "LUCI_PR": "",
+      "OS": "linux",
+      "PUB_CACHE": "[START_DIR]/.pub-cache",
+      "REVISION": "12345abcde12345abcde12345abcde12345abcde",
+      "SDK_CHECKOUT_PATH": "[START_DIR]/flutter"
+    },
+    "env_prefixes": {
+      "PATH": [
+        "[START_DIR]/flutter/bin",
+        "[START_DIR]/flutter/bin/cache/dart-sdk/bin"
+      ]
+    },
+    "name": "test_execution.analyze_logcat",
+    "~followup_annotations": [
+      "@@@STEP_NEST_LEVEL@1@@@"
+    ]
+  },
+  {
+    "name": "$result"
+  }
+]
\ No newline at end of file
diff --git a/recipes/firebaselab/firebaselab.py b/recipes/firebaselab/firebaselab.py
index 42b25b1..41f42bc 100644
--- a/recipes/firebaselab/firebaselab.py
+++ b/recipes/firebaselab/firebaselab.py
@@ -74,12 +74,12 @@
       # SDK 30 is run on a physical redfin/Pixel 5 above.
   ]
 
-  physical_devices = api.properties.get(
+  physical_devices = default_physical_devices if api.properties.get(
       'physical_devices'
-  ) or default_physical_devices
-  virtual_devices = api.properties.get(
+  ) is None else api.properties.get('physical_devices')
+  virtual_devices = default_virtual_devices if api.properties.get(
       'virtual_devices'
-  ) or default_virtual_devices
+  ) is None else api.properties.get('virtual_devices')
 
   test_configurations = (
       (
@@ -119,6 +119,9 @@
           infra_step=True,
       )
       for step_name, build_command, binary, devices in test_configurations:
+        # Skip running gcloud command if no devices were provided.
+        if not devices:
+          continue
         api.step(step_name, build_command)
         firebase_cmd = [
             'firebase', 'test', 'android', 'run', '--type', 'robo', '--app',
@@ -167,6 +170,14 @@
       api.step_data('test_execution.analyze_logcat', retcode=1),
   )
   yield api.test(
+      'empty_devices',
+      api.repo_util.flutter_environment_data(),
+      api.properties(task_name='the_task', virtual_devices=[]),
+      # A return code of 1 from grep means not error messages were
+      # found in logcat and the only acceptable return code.
+      api.step_data('test_execution.analyze_logcat', retcode=1),
+  )
+  yield api.test(
       'succeed_on_infra_failure',
       api.repo_util.flutter_environment_data(),
       api.step_data('test_execution.gcloud firebase', retcode=15),