diff --git a/app/build.gradle b/app/build.gradle
index 135084b..087112e 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -13,7 +13,7 @@ android {
         minSdkVersion 21
         targetSdkVersion 28
         versionCode 12
-        versionName "0.4.0"
+        versionName "0.4.90"
         testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
         resValue "string", "build_time", buildTime()
         setProperty("archivesBaseName", "projectlaogai-$versionName")
@@ -38,6 +38,7 @@ dependencies {
     implementation 'androidx.appcompat:appcompat:1.0.2'
     implementation 'androidx.legacy:legacy-support-v4:1.0.0'
     implementation 'androidx.constraintlayout:constraintlayout:2.0.0-alpha3'
+    implementation 'androidx.swiperefreshlayout:swiperefreshlayout:1.0.0'
     implementation 'com.google.android.material:material:1.0.0'
     implementation 'com.google.code.gson:gson:2.8.5'
     implementation 'com.afollestad:aesthetic:1.0.0-beta05'
diff --git a/app/src/main/AndroidManifest.xml b/app/src/main/AndroidManifest.xml
index 790fe14..d81709c 100644
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@@ -5,6 +5,7 @@
 
     <application
             android:allowBackup="true"
+            android:fullBackupContent="@xml/backup_descriptor"
             android:icon="@mipmap/ic_laogai_icon"
             android:label="@string/app_name"
             android:roundIcon="@mipmap/ic_laogai_icon"
diff --git a/app/src/main/java/org/mosad/seil0/projectlaogai/MainActivity.kt b/app/src/main/java/org/mosad/seil0/projectlaogai/MainActivity.kt
index 5925235..0b6272c 100644
--- a/app/src/main/java/org/mosad/seil0/projectlaogai/MainActivity.kt
+++ b/app/src/main/java/org/mosad/seil0/projectlaogai/MainActivity.kt
@@ -192,7 +192,7 @@ class MainActivity : AppCompatActivity(), NavigationView.OnNavigationItemSelecte
             // update blocking if it's sunday after 1500
             // TODO and the last update was before 1500
             if(currentDay == Calendar.SUNDAY && cal.get(Calendar.HOUR_OF_DAY) >= 15) {
-                val jobA = tcor.getMensa()
+                val jobA = TCoRAPIController.getMensa(this)
                 jobA.get()
             }
 
@@ -205,7 +205,7 @@ class MainActivity : AppCompatActivity(), NavigationView.OnNavigationItemSelecte
                 tcor.getCoursesList()
 
             if(currentTime - mensaCacheTime > 10800)
-                tcor.getMensa()
+                TCoRAPIController.getMensa(this)
 
             if(currentTime - timetableCacheTime > 10800) {
                 tcor.getTimetable(cCourse.courseName, 0)
diff --git a/app/src/main/java/org/mosad/seil0/projectlaogai/controller/CacheController.kt b/app/src/main/java/org/mosad/seil0/projectlaogai/controller/CacheController.kt
index 6bfd192..5c28256 100644
--- a/app/src/main/java/org/mosad/seil0/projectlaogai/controller/CacheController.kt
+++ b/app/src/main/java/org/mosad/seil0/projectlaogai/controller/CacheController.kt
@@ -42,6 +42,29 @@ class CacheController(cont: Context) {
         var mensaCurrentWeek = MensaWeek()
         var mensaNextWeek = MensaWeek()
         var timetables = ArrayList<TimetableWeek>()
+
+        /**
+         * read current and next weeks mensa menus from the cached file
+         */
+        fun readMensa(context: Context) {
+            val file = File(context.filesDir, "mensa.json")
+
+            // make sure the file exists
+            if (!file.exists()) {
+                TCoRAPIController.getMensa(context).get()
+            }
+
+
+            val fileReader = FileReader(file)
+            val bufferedReader = BufferedReader(fileReader)
+            val mensaObject = JsonParser().parse(bufferedReader.readLine()).asJsonObject
+
+            val currentWeek = mensaObject.getAsJsonObject("currentWeek")
+            val nextWeek = mensaObject.getAsJsonObject("nextWeek")
+
+            mensaCurrentWeek = Gson().fromJson(currentWeek, MensaWeek().javaClass)
+            mensaNextWeek = Gson().fromJson(nextWeek, MensaWeek().javaClass)
+        }
     }
 
     /**
@@ -50,7 +73,7 @@ class CacheController(cont: Context) {
      */
     fun readStartCache(courseName: String) {
         readCoursesList()
-        readMensa()
+        readMensa(context)
         readTimetable(courseName, 0)
         readTimetable(courseName, 1)
     }
@@ -59,7 +82,7 @@ class CacheController(cont: Context) {
      * read the courses list from the cached file
      * add them to the coursesList object
      */
-    fun readCoursesList() {
+    private fun readCoursesList() {
         val file = File(context.filesDir, "courses.json")
 
         // make sure the file exists
@@ -73,28 +96,7 @@ class CacheController(cont: Context) {
         coursesList = Gson().fromJson(coursesObject.getAsJsonArray("courses"), object : TypeToken<List<Course>>() {}.type)
     }
 
-    /**
-     * read current and next weeks mensa menus from the cached file
-     */
-    fun readMensa() {
-        val file = File(context.filesDir, "mensa.json")
 
-        // make sure the file exists
-        if (!file.exists()) {
-            TCoRAPIController(context).getMensa().get()
-        }
-
-
-        val fileReader = FileReader(file)
-        val bufferedReader = BufferedReader(fileReader)
-        val mensaObject = JsonParser().parse(bufferedReader.readLine()).asJsonObject
-
-        val currentWeek = mensaObject.getAsJsonObject("currentWeek")
-        val nextWeek = mensaObject.getAsJsonObject("nextWeek")
-
-        mensaCurrentWeek = Gson().fromJson(currentWeek, MensaWeek().javaClass)
-        mensaNextWeek = Gson().fromJson(nextWeek, MensaWeek().javaClass)
-    }
 
     /**
      * read the weeks timetable from the cached file
diff --git a/app/src/main/java/org/mosad/seil0/projectlaogai/controller/TCoRAPIController.kt b/app/src/main/java/org/mosad/seil0/projectlaogai/controller/TCoRAPIController.kt
index 47849af..7391de4 100644
--- a/app/src/main/java/org/mosad/seil0/projectlaogai/controller/TCoRAPIController.kt
+++ b/app/src/main/java/org/mosad/seil0/projectlaogai/controller/TCoRAPIController.kt
@@ -34,6 +34,28 @@ import java.net.URL
 class TCoRAPIController(cont: Context) {
     private val context = cont
 
+    companion object {
+        /**
+         * get the json object from tcor api and write it as file (cache)
+         */
+        fun getMensa(context: Context) = doAsync {
+            val url = URL("https://tcor.mosad.xyz/mensamenu")
+            val file = File(context.filesDir, "mensa.json")
+
+            // read data from the API
+            val mensaObject = JSONObject(url.readText()) //JSONObject(inReader.readLine())
+
+            // write the json object to a file
+            val writer = BufferedWriter(FileWriter(file))
+            writer.write(mensaObject.toString())
+            writer.close()
+
+            // update cache time
+            mensaCacheTime = System.currentTimeMillis() / 1000
+            PreferencesController.save(context)
+        }
+    }
+
     /**
      * get the json object from tcor api and write it as file (cache)
      */
@@ -54,26 +76,6 @@ class TCoRAPIController(cont: Context) {
         PreferencesController.save(context)
     }
 
-    /**
-     * get the json object from tcor api and write it as file (cache)
-     */
-    fun getMensa() = doAsync {
-        val url = URL("https://tcor.mosad.xyz/mensamenu")
-        val file = File(context.filesDir, "mensa.json")
-
-        // read data from the API
-        val mensaObject = JSONObject(url.readText()) //JSONObject(inReader.readLine())
-
-        // write the json object to a file
-        val writer = BufferedWriter(FileWriter(file))
-        writer.write(mensaObject.toString())
-        writer.close()
-
-        // update cache time
-        mensaCacheTime = System.currentTimeMillis() / 1000
-        PreferencesController.save(context)
-    }
-
     /**
      * get the json object from tcor api and write it as file (cache)
      */
diff --git a/app/src/main/java/org/mosad/seil0/projectlaogai/fragments/HomeFragment.kt b/app/src/main/java/org/mosad/seil0/projectlaogai/fragments/HomeFragment.kt
index bf13b26..ab5ac75 100644
--- a/app/src/main/java/org/mosad/seil0/projectlaogai/fragments/HomeFragment.kt
+++ b/app/src/main/java/org/mosad/seil0/projectlaogai/fragments/HomeFragment.kt
@@ -141,7 +141,7 @@ class HomeFragment : Fragment() {
             } else {
                 MaterialDialog(context!!)
                     .title(R.string.error)
-                    .message(R.string.gen_tt_error)
+                    .message(R.string.timetable_error)
                     .show()
                 // TODO log the error and send feedback
             }
diff --git a/app/src/main/java/org/mosad/seil0/projectlaogai/fragments/MensaFragment.kt b/app/src/main/java/org/mosad/seil0/projectlaogai/fragments/MensaFragment.kt
index ef6f3fd..335c6b0 100644
--- a/app/src/main/java/org/mosad/seil0/projectlaogai/fragments/MensaFragment.kt
+++ b/app/src/main/java/org/mosad/seil0/projectlaogai/fragments/MensaFragment.kt
@@ -26,15 +26,15 @@ import android.os.Bundle
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
-import android.widget.LinearLayout
 import androidx.fragment.app.Fragment
 import kotlinx.android.synthetic.main.fragment_mensa.*
 import org.jetbrains.anko.doAsync
 import org.jetbrains.anko.uiThread
-import org.mosad.seil0.projectlaogai.R
+import org.mosad.seil0.projectlaogai.controller.CacheController
 import org.mosad.seil0.projectlaogai.controller.CacheController.Companion.mensaCurrentWeek
 import org.mosad.seil0.projectlaogai.controller.CacheController.Companion.mensaNextWeek
 import org.mosad.seil0.projectlaogai.controller.PreferencesController.Companion.cShowBuffet
+import org.mosad.seil0.projectlaogai.controller.TCoRAPIController
 import org.mosad.seil0.projectlaogai.hsoparser.MensaWeek
 import org.mosad.seil0.projectlaogai.hsoparser.NotRetardedCalendar
 import org.mosad.seil0.projectlaogai.uicomponents.DayCardView
@@ -46,13 +46,12 @@ import org.mosad.seil0.projectlaogai.uicomponents.MealLinearLayout
  */
 class MensaFragment : Fragment() {
 
-    private lateinit var linLayoutMensaFragment: LinearLayout
-
     override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
 
-        val view: View = inflater.inflate(R.layout.fragment_mensa, container, false)
+        val view: View = inflater.inflate(org.mosad.seil0.projectlaogai.R.layout.fragment_mensa, container, false)
 
-        linLayoutMensaFragment = view.findViewById(R.id.linLayout_Mensa)
+        // init actions
+        refreshAction()
 
         // add the current week (week starts on sunday)
         val dayCurrent =  if(NotRetardedCalendar().getDayOfWeekIndex() == 6) 0 else NotRetardedCalendar().getDayOfWeekIndex()
@@ -61,11 +60,15 @@ class MensaFragment : Fragment() {
         // add the next week
         addWeek(mensaNextWeek, 0).get()
 
+        // TODO should we show a info if there is no more food this & next week?
+
         return view
     }
 
     /**
      * add all menus from dayStart to Friday for a given week
+     * @param menusWeek menu of type MensaWeek you want to add
+     * @param dayStart the first day of the week to add
      */
     private fun addWeek(menusWeek: MensaWeek, dayStart: Int) = doAsync {
 
@@ -97,4 +100,41 @@ class MensaFragment : Fragment() {
 
     }
 
+    /**
+     * initialize the refresh action
+     */
+    private fun refreshAction() = doAsync {
+        uiThread {
+
+            // set the refresh listener
+            refreshLayout_Mensa.setOnRefreshListener {
+
+                updateMensaScreen()
+                refreshLayout_Mensa.isRefreshing = false
+
+            }
+
+        }
+    }
+
+    /**
+     * refresh the mensa cache and update the mensa screen
+     * TODO some nice animations
+     */
+    private fun updateMensaScreen() {
+        // update the cache
+        TCoRAPIController.getMensa(context!!)
+        CacheController.readMensa(context!!)
+
+        // remove all menus from the layout
+        linLayout_Mensa.removeAllViews()
+
+        // add the refreshed menus
+        val dayCurrent = if (NotRetardedCalendar().getDayOfWeekIndex() == 6) 0 else NotRetardedCalendar().getDayOfWeekIndex()
+        addWeek(mensaCurrentWeek, dayCurrent).get()
+
+        // add the next week
+        addWeek(mensaNextWeek, 0).get()
+    }
+
 }
diff --git a/app/src/main/res/layout/fragment_mensa.xml b/app/src/main/res/layout/fragment_mensa.xml
index 39e0bde..a9440bd 100644
--- a/app/src/main/res/layout/fragment_mensa.xml
+++ b/app/src/main/res/layout/fragment_mensa.xml
@@ -5,9 +5,10 @@
              android:layout_height="match_parent"
              tools:context=".fragments.MensaFragment">
 
-    <androidx.constraintlayout.widget.ConstraintLayout
+    <androidx.swiperefreshlayout.widget.SwipeRefreshLayout
             android:layout_width="match_parent"
-            android:layout_height="match_parent">
+            android:layout_height="match_parent"
+            android:id="@+id/refreshLayout_Mensa">
 
         <ScrollView
                 android:layout_width="match_parent"
@@ -16,9 +17,9 @@
                     android:orientation="vertical"
                     android:layout_width="match_parent"
                     android:layout_height="wrap_content" android:id="@+id/linLayout_Mensa"
-                    android:background="@color/themePrimary">
-            </LinearLayout>
+                    android:background="@color/themePrimary"/>
         </ScrollView>
-    </androidx.constraintlayout.widget.ConstraintLayout>
+    </androidx.swiperefreshlayout.widget.SwipeRefreshLayout>
+
 
 </FrameLayout>
\ No newline at end of file
diff --git a/app/src/main/res/values-de-rDE/strings.xml b/app/src/main/res/values-de-rDE/strings.xml
index 6432560..85d7943 100644
--- a/app/src/main/res/values-de-rDE/strings.xml
+++ b/app/src/main/res/values-de-rDE/strings.xml
@@ -12,8 +12,7 @@
     <string name="no_more_food">Diese Woche keine weitere Essensausgabe</string>
     <string name="no_lesson_today">heute keine Vorlesung!</string>
     <string name="error">Fehler</string>
-    <string name="no_tt_error">Stundenplan konnte nicht geladen werden!</string>
-    <string name="gen_tt_error">Allgemeiner Stundenplan Fehler!"</string>
+    <string name="timetable_error">Stundenplan konnte nicht geladen werden!</string>
     <string name="info">Info</string>
     <string name="user">Benutzer</string>
     <string name="course_desc">Tippen, um den Kurs zu ändern</string>
diff --git a/app/src/main/res/values/colors.xml b/app/src/main/res/values/colors.xml
index 645a465..7f52220 100644
--- a/app/src/main/res/values/colors.xml
+++ b/app/src/main/res/values/colors.xml
@@ -3,7 +3,6 @@
     <color name="colorPrimary">#000000</color>
     <color name="colorPrimaryDark">#000000</color>
     <color name="colorAccent">#3F51B5</color>
-    <color name="colorMensaDay">#EBE8E9</color>
     <color name="ic_launcher_background">#FFFFFF</color>
 
     <color name="themePrimary">#FFFFFF</color>
@@ -27,6 +26,4 @@
     <color name="themeSecondaryLight">#FFFFFF</color>
     <color name="themeTertiaryLight">#424242</color> <!-- TODO find a better color -->
 
-    <color name="test">#424242</color>
-
 </resources>
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index a5fc160..aadff31 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -20,8 +20,7 @@
 
     <string name="no_lesson_today">"No lecture today!"</string>
     <string name="error">Error</string>
-    <string name="no_tt_error">Could not load timetable!"</string>
-    <string name="gen_tt_error">There was an error with the timetable!"</string>
+    <string name="timetable_error">Could not load timetable!"</string>
 
     <string name="sample_user" translatable="false">SampleUser@stud.hs-offenburg.de</string>
     <string name="sample_course" translatable="false">SampleCourse 3</string>
diff --git a/app/src/main/res/xml/backup_descriptor.xml b/app/src/main/res/xml/backup_descriptor.xml
new file mode 100644
index 0000000..cf29022
--- /dev/null
+++ b/app/src/main/res/xml/backup_descriptor.xml
@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<full-backup-content>
+    <exclude domain="file" path="mensa.json"/>
+    <exclude domain="file" path="courses.json"/>
+</full-backup-content>