diff --git a/android/CHANGELOG.md b/android/CHANGELOG.md
index 23c69dc..7b33be1 100644
--- a/android/CHANGELOG.md
+++ b/android/CHANGELOG.md
@@ -30,3 +30,10 @@
 - Added Room entities: `chats`, `users_short` with sort-friendly indices.
 - Added `ChatDao` with `observeChats()`, `upsertChats()`, and transactional `clearAndReplaceChats()`.
 - Added `MessengerDatabase` and Hilt database wiring (`DatabaseModule`).
+
+### Step 6 - Chat API and repository sync
+- Added chat REST API client for `/api/v1/chats` and `/api/v1/chats/{chat_id}`.
+- Added chat DTOs and remote/local mappers (`ChatReadDto -> ChatEntity/UserShortEntity -> ChatItem`).
+- Implemented `NetworkChatRepository` with cache-first flow strategy (Room first, then server sync).
+- Added chat domain contracts/use-cases (`ChatRepository`, observe/refresh use-cases).
+- Wired chat API/repository via Hilt modules.
diff --git a/android/app/src/main/java/ru/daemonlord/messenger/data/chat/api/ChatApiService.kt b/android/app/src/main/java/ru/daemonlord/messenger/data/chat/api/ChatApiService.kt
new file mode 100644
index 0000000..0abe398
--- /dev/null
+++ b/android/app/src/main/java/ru/daemonlord/messenger/data/chat/api/ChatApiService.kt
@@ -0,0 +1,18 @@
+package ru.daemonlord.messenger.data.chat.api
+
+import retrofit2.http.GET
+import retrofit2.http.Path
+import retrofit2.http.Query
+import ru.daemonlord.messenger.data.chat.dto.ChatReadDto
+
+interface ChatApiService {
+    @GET("/api/v1/chats")
+    suspend fun getChats(
+        @Query("archived") archived: Boolean = false,
+    ): List<ChatReadDto>
+
+    @GET("/api/v1/chats/{chat_id}")
+    suspend fun getChatById(
+        @Path("chat_id") chatId: Long,
+    ): ChatReadDto
+}
diff --git a/android/app/src/main/java/ru/daemonlord/messenger/data/chat/dto/ChatDtos.kt b/android/app/src/main/java/ru/daemonlord/messenger/data/chat/dto/ChatDtos.kt
new file mode 100644
index 0000000..9e0e02b
--- /dev/null
+++ b/android/app/src/main/java/ru/daemonlord/messenger/data/chat/dto/ChatDtos.kt
@@ -0,0 +1,45 @@
+package ru.daemonlord.messenger.data.chat.dto
+
+import kotlinx.serialization.SerialName
+import kotlinx.serialization.Serializable
+
+@Serializable
+data class ChatReadDto(
+    val id: Long,
+    @SerialName("public_id")
+    val publicId: String,
+    val type: String,
+    val title: String? = null,
+    @SerialName("display_title")
+    val displayTitle: String,
+    val handle: String? = null,
+    @SerialName("avatar_url")
+    val avatarUrl: String? = null,
+    val archived: Boolean = false,
+    val pinned: Boolean = false,
+    val muted: Boolean = false,
+    @SerialName("unread_count")
+    val unreadCount: Int = 0,
+    @SerialName("unread_mentions_count")
+    val unreadMentionsCount: Int = 0,
+    @SerialName("counterpart_user_id")
+    val counterpartUserId: Long? = null,
+    @SerialName("counterpart_name")
+    val counterpartName: String? = null,
+    @SerialName("counterpart_username")
+    val counterpartUsername: String? = null,
+    @SerialName("counterpart_avatar_url")
+    val counterpartAvatarUrl: String? = null,
+    @SerialName("counterpart_is_online")
+    val counterpartIsOnline: Boolean? = null,
+    @SerialName("counterpart_last_seen_at")
+    val counterpartLastSeenAt: String? = null,
+    @SerialName("last_message_text")
+    val lastMessageText: String? = null,
+    @SerialName("last_message_type")
+    val lastMessageType: String? = null,
+    @SerialName("last_message_created_at")
+    val lastMessageCreatedAt: String? = null,
+    @SerialName("created_at")
+    val createdAt: String? = null,
+)
diff --git a/android/app/src/main/java/ru/daemonlord/messenger/data/chat/mapper/ChatRemoteMapper.kt b/android/app/src/main/java/ru/daemonlord/messenger/data/chat/mapper/ChatRemoteMapper.kt
new file mode 100644
index 0000000..9319358
--- /dev/null
+++ b/android/app/src/main/java/ru/daemonlord/messenger/data/chat/mapper/ChatRemoteMapper.kt
@@ -0,0 +1,43 @@
+package ru.daemonlord.messenger.data.chat.mapper
+
+import ru.daemonlord.messenger.data.chat.dto.ChatReadDto
+import ru.daemonlord.messenger.data.chat.local.entity.ChatEntity
+import ru.daemonlord.messenger.data.chat.local.entity.UserShortEntity
+
+fun ChatReadDto.toChatEntity(): ChatEntity {
+    return ChatEntity(
+        id = id,
+        publicId = publicId,
+        type = type,
+        title = title,
+        displayTitle = displayTitle,
+        handle = handle,
+        avatarUrl = avatarUrl,
+        archived = archived,
+        pinned = pinned,
+        muted = muted,
+        unreadCount = unreadCount,
+        unreadMentionsCount = unreadMentionsCount,
+        counterpartUserId = counterpartUserId,
+        counterpartName = counterpartName,
+        counterpartUsername = counterpartUsername,
+        counterpartAvatarUrl = counterpartAvatarUrl,
+        counterpartIsOnline = counterpartIsOnline,
+        counterpartLastSeenAt = counterpartLastSeenAt,
+        lastMessageText = lastMessageText,
+        lastMessageType = lastMessageType,
+        lastMessageCreatedAt = lastMessageCreatedAt,
+        updatedSortAt = lastMessageCreatedAt ?: createdAt,
+    )
+}
+
+fun ChatReadDto.toUserShortEntityOrNull(): UserShortEntity? {
+    val userId = counterpartUserId ?: return null
+    val displayName = counterpartName ?: counterpartUsername ?: return null
+    return UserShortEntity(
+        id = userId,
+        displayName = displayName,
+        username = counterpartUsername,
+        avatarUrl = counterpartAvatarUrl,
+    )
+}
diff --git a/android/app/src/main/java/ru/daemonlord/messenger/data/chat/repository/NetworkChatRepository.kt b/android/app/src/main/java/ru/daemonlord/messenger/data/chat/repository/NetworkChatRepository.kt
new file mode 100644
index 0000000..f1f3aa0
--- /dev/null
+++ b/android/app/src/main/java/ru/daemonlord/messenger/data/chat/repository/NetworkChatRepository.kt
@@ -0,0 +1,90 @@
+package ru.daemonlord.messenger.data.chat.repository
+
+import kotlinx.coroutines.CoroutineDispatcher
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.collect
+import kotlinx.coroutines.flow.channelFlow
+import kotlinx.coroutines.withContext
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.channels.awaitClose
+import retrofit2.HttpException
+import ru.daemonlord.messenger.data.chat.api.ChatApiService
+import ru.daemonlord.messenger.data.chat.local.dao.ChatDao
+import ru.daemonlord.messenger.data.chat.mapper.toChatEntity
+import ru.daemonlord.messenger.data.chat.mapper.toDomain
+import ru.daemonlord.messenger.data.chat.mapper.toUserShortEntityOrNull
+import ru.daemonlord.messenger.domain.chat.model.ChatItem
+import ru.daemonlord.messenger.domain.chat.repository.ChatRepository
+import ru.daemonlord.messenger.domain.common.AppError
+import ru.daemonlord.messenger.domain.common.AppResult
+import java.io.IOException
+import javax.inject.Inject
+import javax.inject.Singleton
+
+@Singleton
+class NetworkChatRepository @Inject constructor(
+    private val chatApiService: ChatApiService,
+    private val chatDao: ChatDao,
+    private val ioDispatcher: CoroutineDispatcher = Dispatchers.IO,
+) : ChatRepository {
+
+    override fun observeChats(archived: Boolean): Flow<List<ChatItem>> {
+        return channelFlow {
+            val dbCollection = launch {
+                chatDao.observeChats(archived = archived).collect { rows ->
+                    send(rows.map { it.toDomain() })
+                }
+            }
+            launch(ioDispatcher) {
+                refreshChats(archived = archived)
+            }
+            awaitClose { dbCollection.cancel() }
+        }
+    }
+
+    override suspend fun refreshChats(archived: Boolean): AppResult<Unit> = withContext(ioDispatcher) {
+        try {
+            val chats = chatApiService.getChats(archived = archived)
+            val chatEntities = chats.map { it.toChatEntity() }
+            val userEntities = chats.mapNotNull { it.toUserShortEntityOrNull() }
+            chatDao.clearAndReplaceChats(
+                archived = archived,
+                chats = chatEntities,
+                users = userEntities,
+            )
+            AppResult.Success(Unit)
+        } catch (error: Throwable) {
+            AppResult.Error(error.toAppError())
+        }
+    }
+
+    override suspend fun refreshChat(chatId: Long): AppResult<Unit> = withContext(ioDispatcher) {
+        try {
+            val chat = chatApiService.getChatById(chatId = chatId)
+            chatDao.upsertUsers(chat.toUserShortEntityOrNull()?.let(::listOf).orEmpty())
+            chatDao.upsertChats(listOf(chat.toChatEntity()))
+            AppResult.Success(Unit)
+        } catch (error: Throwable) {
+            AppResult.Error(error.toAppError())
+        }
+    }
+
+    override suspend fun deleteChat(chatId: Long) {
+        withContext(ioDispatcher) {
+            chatDao.deleteChat(chatId = chatId)
+        }
+    }
+
+    private fun Throwable.toAppError(): AppError {
+        return when (this) {
+            is IOException -> AppError.Network
+            is HttpException -> if (code() == 401 || code() == 403) {
+                AppError.Unauthorized
+            } else {
+                AppError.Server(message = message())
+            }
+            else -> AppError.Unknown(cause = this)
+        }
+    }
+}
diff --git a/android/app/src/main/java/ru/daemonlord/messenger/di/NetworkModule.kt b/android/app/src/main/java/ru/daemonlord/messenger/di/NetworkModule.kt
index bb23286..e036a2e 100644
--- a/android/app/src/main/java/ru/daemonlord/messenger/di/NetworkModule.kt
+++ b/android/app/src/main/java/ru/daemonlord/messenger/di/NetworkModule.kt
@@ -13,6 +13,7 @@ import ru.daemonlord.messenger.BuildConfig
 import ru.daemonlord.messenger.core.network.AuthHeaderInterceptor
 import ru.daemonlord.messenger.core.network.TokenRefreshAuthenticator
 import ru.daemonlord.messenger.data.auth.api.AuthApiService
+import ru.daemonlord.messenger.data.chat.api.ChatApiService
 import com.jakewharton.retrofit2.converter.kotlinx.serialization.asConverterFactory
 import java.util.concurrent.TimeUnit
 import javax.inject.Singleton
@@ -108,4 +109,10 @@ object NetworkModule {
     fun provideAuthApiService(retrofit: Retrofit): AuthApiService {
         return retrofit.create(AuthApiService::class.java)
     }
+
+    @Provides
+    @Singleton
+    fun provideChatApiService(retrofit: Retrofit): ChatApiService {
+        return retrofit.create(ChatApiService::class.java)
+    }
 }
diff --git a/android/app/src/main/java/ru/daemonlord/messenger/di/RepositoryModule.kt b/android/app/src/main/java/ru/daemonlord/messenger/di/RepositoryModule.kt
index ce33978..a27da73 100644
--- a/android/app/src/main/java/ru/daemonlord/messenger/di/RepositoryModule.kt
+++ b/android/app/src/main/java/ru/daemonlord/messenger/di/RepositoryModule.kt
@@ -5,7 +5,9 @@ import dagger.Module
 import dagger.hilt.InstallIn
 import dagger.hilt.components.SingletonComponent
 import ru.daemonlord.messenger.data.auth.repository.NetworkAuthRepository
+import ru.daemonlord.messenger.data.chat.repository.NetworkChatRepository
 import ru.daemonlord.messenger.domain.auth.repository.AuthRepository
+import ru.daemonlord.messenger.domain.chat.repository.ChatRepository
 import javax.inject.Singleton
 
 @Module
@@ -17,4 +19,10 @@ abstract class RepositoryModule {
     abstract fun bindAuthRepository(
         repository: NetworkAuthRepository,
     ): AuthRepository
+
+    @Binds
+    @Singleton
+    abstract fun bindChatRepository(
+        repository: NetworkChatRepository,
+    ): ChatRepository
 }
diff --git a/android/app/src/main/java/ru/daemonlord/messenger/domain/chat/repository/ChatRepository.kt b/android/app/src/main/java/ru/daemonlord/messenger/domain/chat/repository/ChatRepository.kt
new file mode 100644
index 0000000..fc8e85e
--- /dev/null
+++ b/android/app/src/main/java/ru/daemonlord/messenger/domain/chat/repository/ChatRepository.kt
@@ -0,0 +1,12 @@
+package ru.daemonlord.messenger.domain.chat.repository
+
+import kotlinx.coroutines.flow.Flow
+import ru.daemonlord.messenger.domain.chat.model.ChatItem
+import ru.daemonlord.messenger.domain.common.AppResult
+
+interface ChatRepository {
+    fun observeChats(archived: Boolean): Flow<List<ChatItem>>
+    suspend fun refreshChats(archived: Boolean): AppResult<Unit>
+    suspend fun refreshChat(chatId: Long): AppResult<Unit>
+    suspend fun deleteChat(chatId: Long)
+}
diff --git a/android/app/src/main/java/ru/daemonlord/messenger/domain/chat/usecase/ObserveChatsUseCase.kt b/android/app/src/main/java/ru/daemonlord/messenger/domain/chat/usecase/ObserveChatsUseCase.kt
new file mode 100644
index 0000000..0e61fee
--- /dev/null
+++ b/android/app/src/main/java/ru/daemonlord/messenger/domain/chat/usecase/ObserveChatsUseCase.kt
@@ -0,0 +1,14 @@
+package ru.daemonlord.messenger.domain.chat.usecase
+
+import kotlinx.coroutines.flow.Flow
+import ru.daemonlord.messenger.domain.chat.model.ChatItem
+import ru.daemonlord.messenger.domain.chat.repository.ChatRepository
+import javax.inject.Inject
+
+class ObserveChatsUseCase @Inject constructor(
+    private val chatRepository: ChatRepository,
+) {
+    operator fun invoke(archived: Boolean): Flow<List<ChatItem>> {
+        return chatRepository.observeChats(archived = archived)
+    }
+}
diff --git a/android/app/src/main/java/ru/daemonlord/messenger/domain/chat/usecase/RefreshChatsUseCase.kt b/android/app/src/main/java/ru/daemonlord/messenger/domain/chat/usecase/RefreshChatsUseCase.kt
new file mode 100644
index 0000000..536c115
--- /dev/null
+++ b/android/app/src/main/java/ru/daemonlord/messenger/domain/chat/usecase/RefreshChatsUseCase.kt
@@ -0,0 +1,13 @@
+package ru.daemonlord.messenger.domain.chat.usecase
+
+import ru.daemonlord.messenger.domain.chat.repository.ChatRepository
+import ru.daemonlord.messenger.domain.common.AppResult
+import javax.inject.Inject
+
+class RefreshChatsUseCase @Inject constructor(
+    private val chatRepository: ChatRepository,
+) {
+    suspend operator fun invoke(archived: Boolean): AppResult<Unit> {
+        return chatRepository.refreshChats(archived = archived)
+    }
+}