diff --git a/mobile-kotlin/app/src/main/java/com/vaultdrop/mobile/features/saf/SafFolderCreator.kt b/mobile-kotlin/app/src/main/java/com/vaultdrop/mobile/features/saf/SafFolderCreator.kt
new file mode 100644
index 0000000..794c058
--- /dev/null
+++ b/mobile-kotlin/app/src/main/java/com/vaultdrop/mobile/features/saf/SafFolderCreator.kt
@@ -0,0 +1,72 @@
+package com.vaultdrop.mobile.features.saf
+
+import android.content.ContentResolver
+import android.content.Context
+import android.content.Intent
+import android.net.Uri
+import android.provider.DocumentsContract
+import dagger.hilt.android.qualifiers.ApplicationContext
+import timber.log.Timber
+import javax.inject.Inject
+import javax.inject.Singleton
+
+/**
+ * Crée un dossier physique via DocumentsContract (SAF) — facteur commun de
+ * `ensureVaultDropFolder` (onboarding) et de la feature « Créer un dossier ».
+ *
+ * Le parent peut être un URI *tree* (racine importée) ou *document* (dossier
+ * déjà créé/parcouru) : les deux sont acceptés par `createDocument`.
+ */
+@Singleton
+class SafFolderCreator @Inject constructor(
+    @ApplicationContext private val context: Context,
+) {
+
+    private val resolver: ContentResolver get() = context.contentResolver
+
+    /**
+     * Crée un sous-dossier nommé `name` sous `parentUri`. Retourne son URI SAF,
+     * ou null si le parent est absente ou si la création échoue.
+     */
+    suspend fun createFolder(parentUri: String?, name: String): Uri? {
+        val parentDocumentUri = toDocumentUri(parentUri) ?: return null
+        val created = runCatching {
+            DocumentsContract.createDocument(
+                resolver,
+                parentDocumentUri,
+                DocumentsContract.Document.MIME_TYPE_DIR,
+                name,
+            )
+        }.getOrElse { e ->
+            Timber.w(e, "cannot create folder '$name' in $parentUri")
+            null
+        } ?: return null
+
+        // Best-effort : prolonge l'accès au-delà de l'intent original.
+        runCatching {
+            resolver.takePersistableUriPermission(
+                created,
+                Intent.FLAG_GRANT_READ_URI_PERMISSION or Intent.FLAG_GRANT_WRITE_URI_PERMISSION,
+            )
+        }.onFailure { Timber.w(it, "persistable uri permission absent for new folder") }
+
+        return created
+    }
+
+    /**
+     * `DocumentsContract.createDocument` attend un URI *document*, pas un URI
+     * *tree*. Convertit un tree URI en document URI (équivalent au dossier
+     * racine de l'arbre) — les deux autorités sont identiques.
+     */
+    private fun toDocumentUri(uri: String?): Uri? {
+        val raw = uri?.let(Uri::parse) ?: return null
+        return if (DocumentsContract.isTreeUri(raw)) {
+            DocumentsContract.buildDocumentUriUsingTree(
+                raw,
+                DocumentsContract.getTreeDocumentId(raw),
+            )
+        } else {
+            raw
+        }
+    }
+}
\ No newline at end of file
diff --git a/mobile-kotlin/app/src/main/java/com/vaultdrop/mobile/ui/components/FolderNameDialog.kt b/mobile-kotlin/app/src/main/java/com/vaultdrop/mobile/ui/components/FolderNameDialog.kt
new file mode 100644
index 0000000..3914dda
--- /dev/null
+++ b/mobile-kotlin/app/src/main/java/com/vaultdrop/mobile/ui/components/FolderNameDialog.kt
@@ -0,0 +1,50 @@
+package com.vaultdrop.mobile.ui.components
+
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.material3.AlertDialog
+import androidx.compose.material3.OutlinedTextField
+import androidx.compose.material3.Text
+import androidx.compose.material3.TextButton
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.res.stringResource
+import com.vaultdrop.mobile.R
+
+/** Dialog de nommage d'un nouveau dossier — partagé accueil / dossier. */
+@Composable
+fun FolderNameDialog(
+    onDismiss: () -> Unit,
+    onConfirm: (String) -> Unit,
+) {
+    var name by remember { mutableStateOf("") }
+    AlertDialog(
+        onDismissRequest = onDismiss,
+        title = { Text(stringResource(R.string.new_folder_name_title)) },
+        text = {
+            OutlinedTextField(
+                value = name,
+                onValueChange = { name = it },
+                placeholder = { Text(stringResource(R.string.new_folder_name_hint)) },
+                singleLine = true,
+                modifier = Modifier.fillMaxWidth(),
+            )
+        },
+        confirmButton = {
+            TextButton(
+                onClick = { onConfirm(name.trim()) },
+                enabled = name.isNotBlank(),
+            ) {
+                Text(stringResource(R.string.create_folder))
+            }
+        },
+        dismissButton = {
+            TextButton(onClick = onDismiss) {
+                Text(stringResource(R.string.pdf_builder_cancel))
+            }
+        },
+    )
+}
\ No newline at end of file