diff --git a/mobile-kotlin/app/src/main/java/com/vaultdrop/mobile/ui/document/DocumentViewerScreen.kt b/mobile-kotlin/app/src/main/java/com/vaultdrop/mobile/ui/document/DocumentViewerScreen.kt
index d45f369..6028099 100644
--- a/mobile-kotlin/app/src/main/java/com/vaultdrop/mobile/ui/document/DocumentViewerScreen.kt
+++ b/mobile-kotlin/app/src/main/java/com/vaultdrop/mobile/ui/document/DocumentViewerScreen.kt
@@ -58,6 +58,8 @@ import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import com.vaultdrop.mobile.R
 import com.vaultdrop.mobile.data.local.entity.FileEntity
 import com.vaultdrop.mobile.domain.FileCategory
+import com.vaultdrop.mobile.features.connection.ConnectionStatusViewModel
+import com.vaultdrop.mobile.ui.components.ServerStatusBadge
 import com.vaultdrop.mobile.ui.components.categoryValue
 import com.vaultdrop.mobile.ui.document.content.DocumentContentViewer
 import com.vaultdrop.mobile.ui.document.content.PdfFocusViewer
@@ -81,9 +83,11 @@ import java.util.Locale
 fun DocumentViewerScreen(
     initialResourceId: String,
     onBack: () -> Unit,
+    connectionStatusViewModel: ConnectionStatusViewModel,
     viewModel: DocumentViewerViewModel = hiltViewModel(),
 ) {
     val documents by viewModel.documents.collectAsStateWithLifecycle()
+    val connectionStatus by connectionStatusViewModel.status.collectAsStateWithLifecycle()
     val pagerState = rememberPagerState(pageCount = { documents.size })
 
     // Démarre une seule fois sur le document demandé, dès que la liste est chargée.
@@ -160,6 +164,12 @@ fun DocumentViewerScreen(
                             )
                         }
                     },
+                    actions = {
+                        ServerStatusBadge(
+                            status = connectionStatus,
+                            onClick = connectionStatusViewModel::checkNow,
+                        )
+                    },
                 )
             }
         },
diff --git a/mobile-kotlin/app/src/main/java/com/vaultdrop/mobile/ui/folderdetail/FolderDetailScreen.kt b/mobile-kotlin/app/src/main/java/com/vaultdrop/mobile/ui/folderdetail/FolderDetailScreen.kt
index 986ba14..e6c69c5 100644
--- a/mobile-kotlin/app/src/main/java/com/vaultdrop/mobile/ui/folderdetail/FolderDetailScreen.kt
+++ b/mobile-kotlin/app/src/main/java/com/vaultdrop/mobile/ui/folderdetail/FolderDetailScreen.kt
@@ -37,7 +37,9 @@ import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import com.vaultdrop.mobile.R
 import com.vaultdrop.mobile.data.local.entity.FileEntity
 import com.vaultdrop.mobile.data.local.entity.FolderEntity
+import com.vaultdrop.mobile.features.connection.ConnectionStatusViewModel
 import com.vaultdrop.mobile.ui.components.FileCategoryIcon
+import com.vaultdrop.mobile.ui.components.ServerStatusBadge
 import java.util.Locale
 
 @OptIn(ExperimentalMaterial3Api::class)
@@ -47,9 +49,11 @@ fun FolderDetailScreen(
     onBack: () -> Unit,
     onOpenFolder: (String) -> Unit,
     onOpenDocument: (String) -> Unit,
+    connectionStatusViewModel: ConnectionStatusViewModel,
     viewModel: FolderDetailViewModel = hiltViewModel(),
 ) {
     val uiState by viewModel.uiState.collectAsStateWithLifecycle()
+    val connectionStatus by connectionStatusViewModel.status.collectAsStateWithLifecycle()
 
     LaunchedEffect(uiState.folderMissing) {
         if (uiState.folderMissing) onBack()
@@ -68,6 +72,10 @@ fun FolderDetailScreen(
                     }
                 },
                 actions = {
+                    ServerStatusBadge(
+                        status = connectionStatus,
+                        onClick = connectionStatusViewModel::checkNow,
+                    )
                     IconButton(onClick = viewModel::refresh) {
                         Icon(Icons.Filled.Refresh, contentDescription = stringResource(R.string.refresh))
                     }
diff --git a/mobile-kotlin/app/src/main/java/com/vaultdrop/mobile/ui/folderlist/FolderListScreen.kt b/mobile-kotlin/app/src/main/java/com/vaultdrop/mobile/ui/folderlist/FolderListScreen.kt
index 038ec8f..c1f71d8 100644
--- a/mobile-kotlin/app/src/main/java/com/vaultdrop/mobile/ui/folderlist/FolderListScreen.kt
+++ b/mobile-kotlin/app/src/main/java/com/vaultdrop/mobile/ui/folderlist/FolderListScreen.kt
@@ -49,8 +49,10 @@ import androidx.hilt.navigation.compose.hiltViewModel
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import com.vaultdrop.mobile.R
 import com.vaultdrop.mobile.data.local.entity.FileEntity
+import com.vaultdrop.mobile.features.connection.ConnectionStatusViewModel
 import com.vaultdrop.mobile.features.sync.SyncViewModel
 import com.vaultdrop.mobile.ui.components.FileCategoryIcon
+import com.vaultdrop.mobile.ui.components.ServerStatusBadge
 import com.vaultdrop.mobile.ui.navigation.FloatingNavBar
 import com.vaultdrop.mobile.ui.navigation.NavTab
 import java.util.Locale
@@ -62,10 +64,12 @@ fun FolderListScreen(
     onTabSelected: (NavTab) -> Unit,
     onOpenDocument: (String) -> Unit,
     syncViewModel: SyncViewModel,
+    connectionStatusViewModel: ConnectionStatusViewModel,
     viewModel: FolderListViewModel = hiltViewModel(),
 ) {
     val uiState by viewModel.uiState.collectAsStateWithLifecycle()
     val importState by syncViewModel.importState.collectAsStateWithLifecycle()
+    val connectionStatus by connectionStatusViewModel.status.collectAsStateWithLifecycle()
     val context = LocalContext.current
     val folderLabel = stringResource(R.string.folder)
 
@@ -91,6 +95,10 @@ fun FolderListScreen(
             TopAppBar(
                 title = { Text(stringResource(R.string.files)) },
                 actions = {
+                    ServerStatusBadge(
+                        status = connectionStatus,
+                        onClick = connectionStatusViewModel::checkNow,
+                    )
                     IconButton(onClick = viewModel::refresh) {
                         Icon(Icons.Filled.Refresh, contentDescription = stringResource(R.string.refresh))
                     }
diff --git a/mobile-kotlin/app/src/main/java/com/vaultdrop/mobile/ui/navigation/NavGraph.kt b/mobile-kotlin/app/src/main/java/com/vaultdrop/mobile/ui/navigation/NavGraph.kt
index cbb7089..eb7625d 100644
--- a/mobile-kotlin/app/src/main/java/com/vaultdrop/mobile/ui/navigation/NavGraph.kt
+++ b/mobile-kotlin/app/src/main/java/com/vaultdrop/mobile/ui/navigation/NavGraph.kt
@@ -15,6 +15,7 @@ import androidx.navigation.compose.currentBackStackEntryAsState
 import androidx.navigation.compose.rememberNavController
 import androidx.navigation.navArgument
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
+import com.vaultdrop.mobile.features.connection.ConnectionStatusViewModel
 import com.vaultdrop.mobile.features.sync.SyncViewModel
 import com.vaultdrop.mobile.ui.auth.AuthViewModel
 import com.vaultdrop.mobile.ui.document.DocumentViewerScreen
@@ -47,6 +48,7 @@ private fun String?.toNavTab(): NavTab = when (this) {
 fun NavGraph(
     authViewModel: AuthViewModel,
     syncViewModel: SyncViewModel,
+    connectionStatusViewModel: ConnectionStatusViewModel,
 ) {
     val navController = rememberNavController()
 
@@ -75,6 +77,7 @@ fun NavGraph(
                     onTabSelected = onTabSelected,
                     onOpenDocument = { id -> navController.navigate(Routes.document(id)) },
                     syncViewModel = syncViewModel,
+                    connectionStatusViewModel = connectionStatusViewModel,
                 )
             }
             composable(Routes.SEARCH) {
@@ -82,6 +85,7 @@ fun NavGraph(
                     selectedTab = selectedTab,
                     onTabSelected = onTabSelected,
                     onOpenDocument = { id -> navController.navigate(Routes.document(id)) },
+                    connectionStatusViewModel = connectionStatusViewModel,
                 )
             }
             composable(Routes.SETTINGS) {
@@ -89,6 +93,7 @@ fun NavGraph(
                     selectedTab = selectedTab,
                     onTabSelected = onTabSelected,
                     authViewModel = authViewModel,
+                    connectionStatusViewModel = connectionStatusViewModel,
                 )
             }
             composable(
@@ -105,6 +110,7 @@ fun NavGraph(
                     onBack = { navController.popBackStack() },
                     onOpenFolder = { id -> navController.navigate(Routes.folder(id)) },
                     onOpenDocument = { id -> navController.navigate(Routes.document(id)) },
+                    connectionStatusViewModel = connectionStatusViewModel,
                 )
             }
             composable(
@@ -119,6 +125,7 @@ fun NavGraph(
                 DocumentViewerScreen(
                     initialResourceId = documentId,
                     onBack = { navController.popBackStack() },
+                    connectionStatusViewModel = connectionStatusViewModel,
                 )
             }
         }
diff --git a/mobile-kotlin/app/src/main/java/com/vaultdrop/mobile/ui/navigation/VaultDropApp.kt b/mobile-kotlin/app/src/main/java/com/vaultdrop/mobile/ui/navigation/VaultDropApp.kt
index f5215f7..61c55f8 100644
--- a/mobile-kotlin/app/src/main/java/com/vaultdrop/mobile/ui/navigation/VaultDropApp.kt
+++ b/mobile-kotlin/app/src/main/java/com/vaultdrop/mobile/ui/navigation/VaultDropApp.kt
@@ -11,6 +11,7 @@ import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.hilt.navigation.compose.hiltViewModel
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
+import com.vaultdrop.mobile.features.connection.ConnectionStatusViewModel
 import com.vaultdrop.mobile.features.sync.SyncViewModel
 import com.vaultdrop.mobile.ui.auth.AuthState
 import com.vaultdrop.mobile.ui.auth.AuthViewModel
@@ -35,18 +36,30 @@ private fun SplashScreen() {
 fun VaultDropApp(
     authViewModel: AuthViewModel = hiltViewModel(),
     syncViewModel: SyncViewModel = hiltViewModel(),
+    connectionStatusViewModel: ConnectionStatusViewModel = hiltViewModel(),
 ) {
     val authState by authViewModel.authState.collectAsStateWithLifecycle()
 
-    // Une fois la session résolue, lancer la boucle de fond (idempotente).
+    // Une fois la session résolue, lancer les boucles de fond (idempotentes).
     LaunchedEffect(authState) {
-        if (authState != AuthState.Loading) syncViewModel.ensureStarted()
+        if (authState != AuthState.Loading) {
+            syncViewModel.ensureStarted()
+            connectionStatusViewModel.start()
+        }
     }
 
     when (authState) {
         AuthState.Loading -> SplashScreen()
         AuthState.SignedOut -> LoginScreen()
-        AuthState.Local -> NavGraph(authViewModel = authViewModel, syncViewModel = syncViewModel)
-        is AuthState.SignedIn -> NavGraph(authViewModel = authViewModel, syncViewModel = syncViewModel)
+        AuthState.Local -> NavGraph(
+            authViewModel = authViewModel,
+            syncViewModel = syncViewModel,
+            connectionStatusViewModel = connectionStatusViewModel,
+        )
+        is AuthState.SignedIn -> NavGraph(
+            authViewModel = authViewModel,
+            syncViewModel = syncViewModel,
+            connectionStatusViewModel = connectionStatusViewModel,
+        )
     }
 }
\ No newline at end of file
diff --git a/mobile-kotlin/app/src/main/java/com/vaultdrop/mobile/ui/search/SearchScreen.kt b/mobile-kotlin/app/src/main/java/com/vaultdrop/mobile/ui/search/SearchScreen.kt
index d92c9dd..28f746c 100644
--- a/mobile-kotlin/app/src/main/java/com/vaultdrop/mobile/ui/search/SearchScreen.kt
+++ b/mobile-kotlin/app/src/main/java/com/vaultdrop/mobile/ui/search/SearchScreen.kt
@@ -44,7 +44,9 @@ import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import com.vaultdrop.mobile.R
 import com.vaultdrop.mobile.data.local.entity.FileEntity
 import com.vaultdrop.mobile.domain.FileCategory
+import com.vaultdrop.mobile.features.connection.ConnectionStatusViewModel
 import com.vaultdrop.mobile.ui.components.FileCategoryIcon
+import com.vaultdrop.mobile.ui.components.ServerStatusBadge
 import com.vaultdrop.mobile.ui.components.color
 import com.vaultdrop.mobile.ui.components.icon
 import com.vaultdrop.mobile.ui.navigation.FloatingNavBar
@@ -57,13 +59,23 @@ fun SearchScreen(
     selectedTab: NavTab,
     onTabSelected: (NavTab) -> Unit,
     onOpenDocument: (String) -> Unit,
+    connectionStatusViewModel: ConnectionStatusViewModel,
     viewModel: SearchViewModel = hiltViewModel(),
 ) {
     val uiState by viewModel.uiState.collectAsStateWithLifecycle()
+    val connectionStatus by connectionStatusViewModel.status.collectAsStateWithLifecycle()
 
     Scaffold(
         topBar = {
-            TopAppBar(title = { Text(stringResource(R.string.search)) })
+            TopAppBar(
+                title = { Text(stringResource(R.string.search)) },
+                actions = {
+                    ServerStatusBadge(
+                        status = connectionStatus,
+                        onClick = connectionStatusViewModel::checkNow,
+                    )
+                },
+            )
         },
         bottomBar = {
             FloatingNavBar(selected = selectedTab, onSelect = onTabSelected)
diff --git a/mobile-kotlin/app/src/main/java/com/vaultdrop/mobile/ui/settings/SettingsScreen.kt b/mobile-kotlin/app/src/main/java/com/vaultdrop/mobile/ui/settings/SettingsScreen.kt
index 296c7e3..350ad9e 100644
--- a/mobile-kotlin/app/src/main/java/com/vaultdrop/mobile/ui/settings/SettingsScreen.kt
+++ b/mobile-kotlin/app/src/main/java/com/vaultdrop/mobile/ui/settings/SettingsScreen.kt
@@ -46,9 +46,11 @@ import androidx.hilt.navigation.compose.hiltViewModel
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import com.vaultdrop.mobile.R
 import com.vaultdrop.mobile.domain.ThemePreference
+import com.vaultdrop.mobile.features.connection.ConnectionStatusViewModel
 import com.vaultdrop.mobile.ui.auth.AuthState
 import com.vaultdrop.mobile.ui.auth.AuthViewModel
 import com.vaultdrop.mobile.ui.auth.authErrorResFor
+import com.vaultdrop.mobile.ui.components.ServerStatusBadge
 import com.vaultdrop.mobile.ui.navigation.FloatingNavBar
 import com.vaultdrop.mobile.ui.navigation.NavTab
 
@@ -58,11 +60,13 @@ fun SettingsScreen(
     selectedTab: NavTab,
     onTabSelected: (NavTab) -> Unit,
     authViewModel: AuthViewModel,
+    connectionStatusViewModel: ConnectionStatusViewModel,
     viewModel: SettingsViewModel = hiltViewModel(),
 ) {
     val theme by viewModel.theme.collectAsStateWithLifecycle()
     val serverUrl by viewModel.serverUrl.collectAsStateWithLifecycle()
     val testUiState by viewModel.testUiState.collectAsStateWithLifecycle()
+    val connectionStatus by connectionStatusViewModel.status.collectAsStateWithLifecycle()
     val authState by authViewModel.authState.collectAsStateWithLifecycle()
     val loginUi by authViewModel.loginUiState.collectAsStateWithLifecycle()
 
@@ -77,7 +81,15 @@ fun SettingsScreen(
 
     Scaffold(
         topBar = {
-            TopAppBar(title = { Text(stringResource(R.string.settings)) })
+            TopAppBar(
+                title = { Text(stringResource(R.string.settings)) },
+                actions = {
+                    ServerStatusBadge(
+                        status = connectionStatus,
+                        onClick = connectionStatusViewModel::checkNow,
+                    )
+                },
+            )
         },
         bottomBar = {
             FloatingNavBar(selected = selectedTab, onSelect = onTabSelected)
diff --git a/mobile-kotlin/app/src/main/res/values/strings.xml b/mobile-kotlin/app/src/main/res/values/strings.xml
index 579b844..4a0bb7b 100644
--- a/mobile-kotlin/app/src/main/res/values/strings.xml
+++ b/mobile-kotlin/app/src/main/res/values/strings.xml
@@ -75,4 +75,11 @@
     <string name="login_error_unauthorized">Nom d\'utilisateur ou mot de passe incorrect</string>
     <string name="login_skip">Continuer sans compte</string>
     <string name="skip_message">Mode local — tes dossiers restent sur cet appareil et ne sont pas synchronisés.</string>
+
+    <!-- Statut serveur (badge du header) -->
+    <string name="status_online">En ligne</string>
+    <string name="status_offline">Hors ligne</string>
+    <string name="status_checking">Vérification…</string>
+    <string name="status_local">Mode local</string>
+    <string name="status_tap_to_recheck">Statut serveur — appuyer pour vérifier</string>
 </resources>
\ No newline at end of file