diff --git a/app/src/main/java/com/indiana/zwl/presentation/AboutScreen.kt b/app/src/main/java/com/indiana/zwl/presentation/AboutScreen.kt
index 6dba24b..26e071f 100644
--- a/app/src/main/java/com/indiana/zwl/presentation/AboutScreen.kt
+++ b/app/src/main/java/com/indiana/zwl/presentation/AboutScreen.kt
@@ -52,9 +52,11 @@ import androidx.compose.ui.unit.dp
 import androidx.compose.ui.unit.sp
 import com.indiana.zwl.BuildConfig
 import com.indiana.zwl.R
+import com.indiana.zwl.domain.model.WaterDataState
 import com.indiana.zwl.presentation.theme.DarkForestBackground
 import com.indiana.zwl.presentation.theme.ForestGreenAccent
 import com.indiana.zwl.presentation.theme.ForestGreenText
+import com.indiana.zwl.shared.data.water.WaterAttribution
 
 private const val BDL_PORTAL_URL = "https://www.bdl.lasy.gov.pl/portal/"
 private const val IBL_FIRE_URL = "https://bazapozarow.ibles.pl/"
@@ -67,6 +69,7 @@ private const val INSTAGRAM_URL = "https://instagram.com/legalny.bushcraft"
 @Composable
 fun AboutScreen(
     onClose: () -> Unit,
+    waterDataState: WaterDataState? = null,
     modifier: Modifier = Modifier
 ) {
     val isLandscape =
@@ -205,6 +208,50 @@ fun AboutScreen(
                 }
             }
 
+            Card(
+                modifier = Modifier.fillMaxWidth(),
+                colors = CardDefaults.cardColors(containerColor = MaterialTheme.colorScheme.surface),
+                shape = RoundedCornerShape(12.dp)
+            ) {
+                Column(
+                    modifier = Modifier.padding(16.dp),
+                    verticalArrangement = Arrangement.spacedBy(10.dp)
+                ) {
+                    Row(verticalAlignment = Alignment.CenterVertically) {
+                        Icon(
+                            imageVector = Icons.Default.Public,
+                            contentDescription = null,
+                            tint = ForestGreenAccent,
+                            modifier = Modifier.size(20.dp)
+                        )
+                        Spacer(modifier = Modifier.width(8.dp))
+                        Text(
+                            text = "Dane źródeł wody (OSM)",
+                            fontSize = 15.sp,
+                            fontWeight = FontWeight.Bold,
+                            color = MaterialTheme.colorScheme.onSurface
+                        )
+                    }
+
+                    Text(
+                        text = "Punkty wody pitnej, źródeł, studni i napełniania butelek pochodzą z OpenStreetMap i odświeżają się automatycznie.",
+                        fontSize = 13.sp,
+                        color = MaterialTheme.colorScheme.onSurfaceVariant,
+                        lineHeight = 19.sp
+                    )
+
+                    DataRow(label = "Wersja danych", value = waterVersionLabel(waterDataState?.dataVersion))
+                    DataRow(label = "Data pobrania", value = waterFetchedAtLabel(waterDataState?.lastCheckedAt))
+                    DataRow(label = "Liczba punktów", value = waterDataState?.count?.toString() ?: "—")
+
+                    Text(
+                        text = WaterAttribution.OSM,
+                        fontSize = 11.sp,
+                        color = MaterialTheme.colorScheme.onSurfaceVariant
+                    )
+                }
+            }
+
             Card(
                 modifier = Modifier.fillMaxWidth(),
                 colors = CardDefaults.cardColors(containerColor = MaterialTheme.colorScheme.surface),
@@ -377,3 +424,38 @@ private fun SourceLinkRow(label: String, url: String) {
         )
     }
 }
+
+@Composable
+private fun DataRow(label: String, value: String) {
+    Row(
+        modifier = Modifier.fillMaxWidth(),
+        horizontalArrangement = Arrangement.SpaceBetween,
+        verticalAlignment = Alignment.CenterVertically
+    ) {
+        Text(
+            text = label,
+            fontSize = 13.sp,
+            color = MaterialTheme.colorScheme.onSurfaceVariant
+        )
+        Text(
+            text = value,
+            fontSize = 13.sp,
+            fontWeight = FontWeight.Medium,
+            color = MaterialTheme.colorScheme.onSurface
+        )
+    }
+}
+
+private fun waterVersionLabel(version: Long?): String {
+    if (version == null || version <= 0L) return "—"
+    val year = version / 10000
+    val month = (version / 100) % 100
+    val day = version % 100
+    return String.format(java.util.Locale.US, "%04d-%02d-%02d", year, month, day)
+}
+
+private fun waterFetchedAtLabel(millis: Long?): String {
+    if (millis == null || millis <= 0L) return "zestaw wbudowany"
+    return java.text.SimpleDateFormat("yyyy-MM-dd HH:mm", java.util.Locale.getDefault())
+        .format(java.util.Date(millis))
+}
diff --git a/app/src/main/java/com/indiana/zwl/presentation/MainScreen.kt b/app/src/main/java/com/indiana/zwl/presentation/MainScreen.kt
index ed3bdcf..e0b94f8 100644
--- a/app/src/main/java/com/indiana/zwl/presentation/MainScreen.kt
+++ b/app/src/main/java/com/indiana/zwl/presentation/MainScreen.kt
@@ -236,6 +236,7 @@ fun MainScreen(
             val savedPoints by viewModel.savedPoints.collectAsStateWithLifecycle()
             val showSavedPointList by viewModel.showSavedPointList.collectAsStateWithLifecycle()
             val selectedSavedPointInfo by viewModel.selectedSavedPointInfo.collectAsStateWithLifecycle()
+            val waterDataState by viewModel.waterDataState.collectAsStateWithLifecycle()
             val savedPointDetailViewModel: SavedPointDetailViewModel = hiltViewModel()
             val selectedSavedPointDetails by savedPointDetailViewModel.details.collectAsStateWithLifecycle()
             var selectedTab by rememberSaveable { mutableStateOf(0) }
@@ -459,7 +460,10 @@ fun MainScreen(
                                 )
 
                                 if (showAbout) {
-                                    AboutScreen(onClose = { showAbout = false })
+                                    AboutScreen(
+                                        waterDataState = waterDataState,
+                                        onClose = { showAbout = false }
+                                    )
                                 }
 
                                 if (showSavedPointList) {
diff --git a/app/src/main/java/com/indiana/zwl/presentation/MainViewModel.kt b/app/src/main/java/com/indiana/zwl/presentation/MainViewModel.kt
index 1749118..4f14da4 100644
--- a/app/src/main/java/com/indiana/zwl/presentation/MainViewModel.kt
+++ b/app/src/main/java/com/indiana/zwl/presentation/MainViewModel.kt
@@ -17,6 +17,7 @@ import com.indiana.zwl.domain.model.Zone
 import com.indiana.zwl.domain.model.Poi
 import com.indiana.zwl.domain.model.SavedPoint
 import com.indiana.zwl.domain.model.NewSavedPoint
+import com.indiana.zwl.domain.model.WaterDataState
 import com.indiana.zwl.domain.model.WaterSource
 import com.indiana.zwl.shared.data.water.WaterSyncManager
 import com.indiana.zwl.domain.usecase.GetFireRiskUseCase
@@ -288,6 +289,15 @@ class MainViewModel @Inject constructor(
         }
     }.stateIn(viewModelScope, SharingStarted.WhileSubscribed(5000), emptyList())
 
+    private val _waterDataState = MutableStateFlow<WaterDataState?>(null)
+    val waterDataState: StateFlow<WaterDataState?> = _waterDataState.asStateFlow()
+
+    fun refreshWaterDataState() {
+        viewModelScope.launch {
+            _waterDataState.value = waterSourceRepository.getDataState()
+        }
+    }
+
     private val _showPoiGroups = MutableStateFlow(
         PoiUiGroup.entries.associateWith { sharedPrefs.getBoolean("show_poi_${it.key}", true) }
     )
@@ -451,6 +461,7 @@ class MainViewModel @Inject constructor(
 
     init {
         loadZonesAndInitializeEngine()
+        refreshWaterDataState()
     }
 
     fun setLocationPermissionGranted(granted: Boolean) {
@@ -484,6 +495,7 @@ class MainViewModel @Inject constructor(
             viewModelScope.launch(ioDispatcher) {
                 try {
                     waterSyncManager.ensureBaselineIfEmpty()
+                    refreshWaterDataState()
                 } catch (e: Exception) {
                     if (e is CancellationException) throw e
                     e.printStackTrace()
@@ -544,6 +556,7 @@ class MainViewModel @Inject constructor(
             viewModelScope.launch(ioDispatcher) {
                 try {
                     waterSyncManager.refreshIfStale()
+                    refreshWaterDataState()
                 } catch (e: Exception) {
                     if (e is CancellationException) throw e
                     e.printStackTrace()
diff --git a/iosApp/iosApp/ViewModels/MainViewModel.swift b/iosApp/iosApp/ViewModels/MainViewModel.swift
index b660156..5c29a3b 100644
--- a/iosApp/iosApp/ViewModels/MainViewModel.swift
+++ b/iosApp/iosApp/ViewModels/MainViewModel.swift
@@ -55,6 +55,7 @@ final class MainViewModel: NSObject, ObservableObject {
     @Published var bansGeoJson: String = ""
     @Published var poisGeoJson: String = ""
     @Published var waterGeoJson: String = ""
+    @Published var waterDataState: WaterDataState?
 
     // Layer toggles (persisted across launches like Android's
     // SharedPreferences `zwl_map_settings`; they reset to defaults only on
@@ -373,6 +374,7 @@ final class MainViewModel: NSObject, ObservableObject {
             includeDrinking: showWaterDrinking,
             includeSprings: showWaterSprings,
             includeWells: showWaterWells)) ?? ""
+        waterDataState = (try? await app.waterDataState()) ?? nil
         guard let zones = try? await app.zonesGeoJson(),
               let bans = try? await app.bansGeoJson(),
               let pois = try? await app.poisGeoJson() else { return }
diff --git a/iosApp/iosApp/Views/AboutView.swift b/iosApp/iosApp/Views/AboutView.swift
index 347d0cc..cbdbe24 100644
--- a/iosApp/iosApp/Views/AboutView.swift
+++ b/iosApp/iosApp/Views/AboutView.swift
@@ -1,8 +1,10 @@
 import SwiftUI
+import shared
 
 /// "O aplikacji" (Android `AboutScreen` parity): legal disclaimer, data
 /// sources with tappable links, privacy note and the app version footer.
 struct AboutView: View {
+    let waterDataState: WaterDataState?
     @Environment(\.dismiss) private var dismiss
 
     private let bdlPortalUrl = URL(string: "https://www.bdl.lasy.gov.pl/portal/")!
@@ -37,6 +39,19 @@ struct AboutView: View {
                     sectionHeader("Źródła danych rządowych", systemImage: "globe")
                 }
 
+                Section {
+                    Text("Punkty wody pitnej, źródeł, studni i napełniania butelek pochodzą z OpenStreetMap i odświeżają się automatycznie.")
+                        .font(.system(size: 13))
+                    dataRow("Wersja danych", waterDataState.map { waterVersionLabel($0.dataVersion) } ?? "—")
+                    dataRow("Data pobrania", waterDataState.map { waterFetchedAtLabel($0.lastCheckedAt) } ?? "zestaw wbudowany")
+                    dataRow("Liczba punktów", waterDataState.map { String($0.count) } ?? "—")
+                    Text(WaterAttribution.shared.OSM)
+                        .font(.system(size: 11))
+                        .foregroundColor(.secondary)
+                } header: {
+                    sectionHeader("Dane źródeł wody (OSM)", systemImage: "drop")
+                }
+
                 Section {
                     Text("Twoja lokalizacja służy wyłącznie do sprawdzenia stref i jest przetwarzana lokalnie na urządzeniu. Aby pokazać zagrożenie pożarowe, aplikacja wysyła anonimowe zapytanie z Twoimi współrzędnymi do publicznego API BDL — bez tworzenia profili i bez zapisu historii lokalizacji. Aplikacja nie zawiera reklam ani systemów analitycznych.")
                         .font(.system(size: 13))
@@ -102,6 +117,32 @@ struct AboutView: View {
         Bundle.main.object(forInfoDictionaryKey: "CFBundleShortVersionString") as? String ?? "—"
     }
 
+    private func dataRow(_ label: String, _ value: String) -> some View {
+        HStack {
+            Text(label)
+                .font(.system(size: 13))
+                .foregroundColor(.secondary)
+            Spacer()
+            Text(value)
+                .font(.system(size: 13, weight: .medium))
+        }
+    }
+
+    private func waterVersionLabel(_ version: Int64) -> String {
+        guard version > 0 else { return "—" }
+        let year = version / 10000
+        let month = (version / 100) % 100
+        let day = version % 100
+        return String(format: "%04d-%02d-%02d", year, month, day)
+    }
+
+    private func waterFetchedAtLabel(_ millis: Int64) -> String {
+        guard millis > 0 else { return "zestaw wbudowany" }
+        let formatter = DateFormatter()
+        formatter.dateFormat = "yyyy-MM-dd HH:mm"
+        return formatter.string(from: Date(timeIntervalSince1970: TimeInterval(millis) / 1000.0))
+    }
+
     private func sectionHeader(_ title: String, systemImage: String) -> some View {
         Label(title, systemImage: systemImage)
             .font(.system(size: 13, weight: .bold))
diff --git a/iosApp/iosApp/Views/MainView.swift b/iosApp/iosApp/Views/MainView.swift
index 5f29dd9..75e7f12 100644
--- a/iosApp/iosApp/Views/MainView.swift
+++ b/iosApp/iosApp/Views/MainView.swift
@@ -114,7 +114,7 @@ struct MainView: View {
             OfflineAreasView(viewModel: viewModel)
         }
         .fullScreenCover(isPresented: $showAbout) {
-            AboutView()
+            AboutView(waterDataState: viewModel.waterDataState)
         }
         .alert("Obszar za duży", isPresented: Binding(
             get: { viewModel.downloadBlockedMessage != nil },
diff --git a/shared/src/iosMain/kotlin/com/indiana/zwl/shared/ios/ForestApp.kt b/shared/src/iosMain/kotlin/com/indiana/zwl/shared/ios/ForestApp.kt
index bd330c0..e593603 100644
--- a/shared/src/iosMain/kotlin/com/indiana/zwl/shared/ios/ForestApp.kt
+++ b/shared/src/iosMain/kotlin/com/indiana/zwl/shared/ios/ForestApp.kt
@@ -9,6 +9,7 @@ import com.indiana.zwl.domain.model.NewSavedPoint
 import com.indiana.zwl.domain.model.Poi
 import com.indiana.zwl.domain.model.SavedPoint
 import com.indiana.zwl.domain.model.SoilCover
+import com.indiana.zwl.domain.model.WaterDataState
 import com.indiana.zwl.domain.model.WaterSource
 import com.indiana.zwl.domain.model.Zone
 import com.indiana.zwl.domain.repository.ForestBanRepository
@@ -246,6 +247,8 @@ class ForestApp(
 
     fun cachedWaterSources(): List<WaterSource> = cachedWaterSources
 
+    suspend fun waterDataState(): WaterDataState? = waterSourceRepository.getDataState()
+
     suspend fun syncZones(): Boolean = withContext(Dispatchers.Default) {
         try {
             val responseStr = arcgisApi.getZanocujWLesieZones()