diff --git a/Ledger/app/build.gradle.kts b/Ledger/app/build.gradle.kts
index b0b0628..8e4824d 100644
--- a/Ledger/app/build.gradle.kts
+++ b/Ledger/app/build.gradle.kts
@@ -59,6 +59,8 @@ dependencies {
     implementation(libs.androidx.ui.graphics)
     implementation(libs.androidx.ui.tooling.preview)
     implementation(libs.androidx.material3)
+    implementation(libs.androidx.room.common)
+    implementation(libs.androidx.room.ktx)
     testImplementation(libs.junit)
     androidTestImplementation(libs.androidx.junit)
     androidTestImplementation(libs.androidx.espresso.core)
diff --git a/Ledger/app/src/main/java/at/xaxa/ledger/LedgerApplication.kt b/Ledger/app/src/main/java/at/xaxa/ledger/LedgerApplication.kt
new file mode 100644
index 0000000..ac08f41
--- /dev/null
+++ b/Ledger/app/src/main/java/at/xaxa/ledger/LedgerApplication.kt
@@ -0,0 +1,13 @@
+package at.xaxa.ledger
+
+import android.app.Application
+import at.xaxa.ledger.data.EntryRepository
+import at.xaxa.ledger.data.db.LedgerDatabase
+
+class LedgerApplication : Application(){
+    val entryRepository by lazy {
+        EntryRepository(
+            DatabaseInstance.getDatabase(this).LedgerDao()
+        )
+    }
+}
\ No newline at end of file
diff --git a/Ledger/app/src/main/java/at/xaxa/ledger/data/Entry.kt b/Ledger/app/src/main/java/at/xaxa/ledger/data/Entry.kt
new file mode 100644
index 0000000..8b65621
--- /dev/null
+++ b/Ledger/app/src/main/java/at/xaxa/ledger/data/Entry.kt
@@ -0,0 +1,9 @@
+package at.xaxa.ledger.data
+
+class Entry (
+    val id: Int,
+    val name: String,
+    val amount: Float,
+    val date: Long,
+    val categoryName: Int
+)
\ No newline at end of file
diff --git a/Ledger/app/src/main/java/at/xaxa/ledger/data/EntryRepository.kt b/Ledger/app/src/main/java/at/xaxa/ledger/data/EntryRepository.kt
new file mode 100644
index 0000000..27b5128
--- /dev/null
+++ b/Ledger/app/src/main/java/at/xaxa/ledger/data/EntryRepository.kt
@@ -0,0 +1,35 @@
+package at.xaxa.ledger.data
+
+import at.xaxa.ledger.data.db.Entry.EntryEntity
+import at.xaxa.ledger.data.db.LedgerDao
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.map
+
+
+class EntryRepository(private val ledgerDao: LedgerDao){
+
+
+    fun getAllEntries(): Flow<List<Entry>> {
+        return ledgerDao.getAllEntries().map {
+            it.map {entry -> Entry(entry._id, entry.name, entry.amount, entry.date, entry.categoryName) }
+        }
+    }
+
+    suspend fun findEntryById(id: Int): Entry {
+        val entry = LedgerDao.findEntryById(id)
+        return Entry(
+            entry._id, entry.name, entry.amount, entry.date, entry.categoryName
+        )
+    }
+    suspend fun insertEntry(entry: Entry) {
+        LedgerDao.addEntry(EntryEntity(_id=0, entry.name, entry.amount, entry.date, entry.categoryName))
+    }
+
+    suspend fun updateEntry(entry: Entry) {
+        LedgerDao.updateEntry(EntryEntity(entry.id, entry.name, entry.amount, entry.date, entry.categoryName))
+    }
+    suspend fun deletePokemon(entry: Entry) {
+        LedgerDao.deleteEntry(EntryEntity(_id = entry.id, entry.name, entry.amount, entry.date, entry.categoryName))
+    }
+
+}
\ No newline at end of file
diff --git a/Ledger/app/src/main/java/at/xaxa/ledger/data/db/Category/CategoryEntity.kt b/Ledger/app/src/main/java/at/xaxa/ledger/data/db/Category/CategoryEntity.kt
new file mode 100644
index 0000000..d1aed3c
--- /dev/null
+++ b/Ledger/app/src/main/java/at/xaxa/ledger/data/db/Category/CategoryEntity.kt
@@ -0,0 +1,12 @@
+package at.xaxa.ledger.data.db.Category
+
+import androidx.room.Entity
+import androidx.room.PrimaryKey
+
+@Entity(tableName = "category")
+data class CategoryEntity(
+    @PrimaryKey(autoGenerate = true)
+    val _id: Int = 0,
+    val categoryname: String,
+    val icon: Int
+)
\ No newline at end of file
diff --git a/Ledger/app/src/main/java/at/xaxa/ledger/data/db/DatabaseInstance.kt b/Ledger/app/src/main/java/at/xaxa/ledger/data/db/DatabaseInstance.kt
new file mode 100644
index 0000000..2ca0847
--- /dev/null
+++ b/Ledger/app/src/main/java/at/xaxa/ledger/data/db/DatabaseInstance.kt
@@ -0,0 +1,20 @@
+import android.content.Context
+import androidx.room.Room
+import at.xaxa.ledger.data.db.LedgerDatabase
+
+object DatabaseInstance {
+    @Volatile
+    private var INSTANCE: LedgerDatabase? = null
+
+    fun getDatabase(context: Context): LedgerDatabase {
+        return INSTANCE ?: synchronized(this) {
+            val instance = Room.databaseBuilder(
+                context.applicationContext,
+                LedgerDatabase::class.java,
+                "ledger_database"
+            ).build()
+            INSTANCE = instance
+            instance
+        }
+    }
+}
\ No newline at end of file
diff --git a/Ledger/app/src/main/java/at/xaxa/ledger/data/db/Entry/EntryEntity.kt b/Ledger/app/src/main/java/at/xaxa/ledger/data/db/Entry/EntryEntity.kt
new file mode 100644
index 0000000..aaa68c2
--- /dev/null
+++ b/Ledger/app/src/main/java/at/xaxa/ledger/data/db/Entry/EntryEntity.kt
@@ -0,0 +1,14 @@
+package at.xaxa.ledger.data.db.Entry
+
+import androidx.room.Entity
+import androidx.room.PrimaryKey
+
+@Entity(tableName = "transaction")
+data class EntryEntity(
+    @PrimaryKey(autoGenerate = true)
+    val _id: Int = 0,
+    val name: String,
+    val amount: Float,
+    val date: Long,
+    val categoryName: Int
+)
\ No newline at end of file
diff --git a/Ledger/app/src/main/java/at/xaxa/ledger/data/db/LedgerDao.kt b/Ledger/app/src/main/java/at/xaxa/ledger/data/db/LedgerDao.kt
new file mode 100644
index 0000000..de68f4c
--- /dev/null
+++ b/Ledger/app/src/main/java/at/xaxa/ledger/data/db/LedgerDao.kt
@@ -0,0 +1,50 @@
+package at.xaxa.ledger.data.db
+
+import androidx.room.Dao
+import androidx.room.Delete
+import androidx.room.Insert
+import androidx.room.OnConflictStrategy
+import androidx.room.Query
+import androidx.room.Update
+import at.xaxa.ledger.data.db.Category.CategoryEntity
+import at.xaxa.ledger.data.db.Entry.EntryEntity
+import kotlinx.coroutines.flow.Flow
+
+@Dao
+interface LedgerDao {
+    @Insert(onConflict = OnConflictStrategy.IGNORE)
+    suspend fun addCategory(entryEntity: CategoryEntity)
+
+    @Insert(onConflict = OnConflictStrategy.IGNORE)
+    suspend fun addEntry(entryEntity: EntryEntity)
+
+    @Update
+    suspend fun updateCategory(category: CharCategory)
+
+    @Update
+    suspend fun updateEntry(entryEntity: EntryEntity)
+
+
+    @Delete
+    suspend fun deleteCategory(category: CharCategory)
+
+
+    @Delete
+    suspend fun deleteEntry(entryEntity: EntryEntity)
+
+
+    @Query("SELECT * FROM category WHERE _id = :id")
+    suspend fun findCategoryById(id: Int) : CategoryEntity
+
+
+    @Query("SELECT * FROM category")
+    fun getAllCategory(): Flow<List<CategoryEntity>>
+
+
+    @Query("SELECT * FROM transaction WHERE _id = :id")
+    suspend fun findEntryById(id: Int) : EntryEntity
+
+
+    @Query("SELECT * FROM transaction")
+    fun getAllEntries(): Flow<List<EntryEntity>>
+}
diff --git a/Ledger/app/src/main/java/at/xaxa/ledger/data/db/LedgerDatabase.kt b/Ledger/app/src/main/java/at/xaxa/ledger/data/db/LedgerDatabase.kt
new file mode 100644
index 0000000..f3744fd
--- /dev/null
+++ b/Ledger/app/src/main/java/at/xaxa/ledger/data/db/LedgerDatabase.kt
@@ -0,0 +1,12 @@
+package at.xaxa.ledger.data.db
+
+import androidx.room.Database
+import androidx.room.RoomDatabase
+import at.xaxa.ledger.data.db.Category.CategoryEntity
+import at.xaxa.ledger.data.db.Entry.EntryEntity
+
+@Database(entities = [EntryEntity::class, CategoryEntity::class], version = 1, exportSchema = false)
+abstract class LedgerDatabase : RoomDatabase() {
+    abstract fun entryDao(): EntryDao
+    abstract fun categoryDao(): CategoryDao
+}
\ No newline at end of file
diff --git a/Ledger/app/src/main/java/at/xaxa/ledger/ui/AppViewModelProvider.kt b/Ledger/app/src/main/java/at/xaxa/ledger/ui/AppViewModelProvider.kt
new file mode 100644
index 0000000..51c31cc
--- /dev/null
+++ b/Ledger/app/src/main/java/at/xaxa/ledger/ui/AppViewModelProvider.kt
@@ -0,0 +1,5 @@
+package at.xaxa.ledger.ui
+
+object AppViewModelProvider {
+
+}
\ No newline at end of file
diff --git a/Ledger/app/src/main/java/at/xaxa/ledger/ui/add/AddUI.kt b/Ledger/app/src/main/java/at/xaxa/ledger/ui/add/AddUI.kt
new file mode 100644
index 0000000..bea04de
--- /dev/null
+++ b/Ledger/app/src/main/java/at/xaxa/ledger/ui/add/AddUI.kt
@@ -0,0 +1,2 @@
+package at.xaxa.ledger.ui.add
+
diff --git a/Ledger/app/src/main/java/at/xaxa/ledger/ui/add/AddViewModel.kt b/Ledger/app/src/main/java/at/xaxa/ledger/ui/add/AddViewModel.kt
new file mode 100644
index 0000000..bea04de
--- /dev/null
+++ b/Ledger/app/src/main/java/at/xaxa/ledger/ui/add/AddViewModel.kt
@@ -0,0 +1,2 @@
+package at.xaxa.ledger.ui.add
+
diff --git a/Ledger/app/src/main/java/at/xaxa/ledger/ui/edit/EditUI.kt b/Ledger/app/src/main/java/at/xaxa/ledger/ui/edit/EditUI.kt
new file mode 100644
index 0000000..772c30d
--- /dev/null
+++ b/Ledger/app/src/main/java/at/xaxa/ledger/ui/edit/EditUI.kt
@@ -0,0 +1,2 @@
+package at.xaxa.ledger.ui.edit
+
diff --git a/Ledger/app/src/main/java/at/xaxa/ledger/ui/edit/EditViewModel.kt b/Ledger/app/src/main/java/at/xaxa/ledger/ui/edit/EditViewModel.kt
new file mode 100644
index 0000000..772c30d
--- /dev/null
+++ b/Ledger/app/src/main/java/at/xaxa/ledger/ui/edit/EditViewModel.kt
@@ -0,0 +1,2 @@
+package at.xaxa.ledger.ui.edit
+
diff --git a/Ledger/app/src/main/java/at/xaxa/ledger/ui/home/HomeUI.kt b/Ledger/app/src/main/java/at/xaxa/ledger/ui/home/HomeUI.kt
new file mode 100644
index 0000000..1928f38
--- /dev/null
+++ b/Ledger/app/src/main/java/at/xaxa/ledger/ui/home/HomeUI.kt
@@ -0,0 +1,2 @@
+package at.xaxa.ledger.ui.home
+
diff --git a/Ledger/app/src/main/java/at/xaxa/ledger/ui/home/HomeViewModel.kt b/Ledger/app/src/main/java/at/xaxa/ledger/ui/home/HomeViewModel.kt
new file mode 100644
index 0000000..1928f38
--- /dev/null
+++ b/Ledger/app/src/main/java/at/xaxa/ledger/ui/home/HomeViewModel.kt
@@ -0,0 +1,2 @@
+package at.xaxa.ledger.ui.home
+
diff --git a/Ledger/gradle/libs.versions.toml b/Ledger/gradle/libs.versions.toml
index 4b06795..426c4de 100644
--- a/Ledger/gradle/libs.versions.toml
+++ b/Ledger/gradle/libs.versions.toml
@@ -8,6 +8,8 @@ espressoCore = "3.6.1"
 lifecycleRuntimeKtx = "2.8.7"
 activityCompose = "1.9.3"
 composeBom = "2024.04.01"
+roomCommon = "2.6.1"
+roomKtx = "2.6.1"
 
 [libraries]
 androidx-core-ktx = { group = "androidx.core", name = "core-ktx", version.ref = "coreKtx" }
@@ -24,6 +26,8 @@ androidx-ui-tooling-preview = { group = "androidx.compose.ui", name = "ui-toolin
 androidx-ui-test-manifest = { group = "androidx.compose.ui", name = "ui-test-manifest" }
 androidx-ui-test-junit4 = { group = "androidx.compose.ui", name = "ui-test-junit4" }
 androidx-material3 = { group = "androidx.compose.material3", name = "material3" }
+androidx-room-common = { group = "androidx.room", name = "room-common", version.ref = "roomCommon" }
+androidx-room-ktx = { group = "androidx.room", name = "room-ktx", version.ref = "roomKtx" }
 
 [plugins]
 android-application = { id = "com.android.application", version.ref = "agp" }