diff --git a/app/build.gradle b/app/build.gradle
index eaf0cae3..c64eec87 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -164,6 +164,7 @@ dependencies {
     implementation "eu.davidea:flexible-adapter-ui:1.0.0"
     implementation "com.aurelhubert:ahbottomnavigation:2.3.4"
     implementation "com.ncapdevi:frag-nav:3.3.0"
+    implementation "com.github.YarikSOffice:lingver:1.1.0"
 
     implementation "com.github.pwittchen:reactivenetwork-rx2:3.0.6"
     implementation "io.reactivex.rxjava2:rxandroid:2.1.1"
diff --git a/app/src/main/java/io/github/wulkanowy/WulkanowyApp.kt b/app/src/main/java/io/github/wulkanowy/WulkanowyApp.kt
index 72969059..90b3581c 100644
--- a/app/src/main/java/io/github/wulkanowy/WulkanowyApp.kt
+++ b/app/src/main/java/io/github/wulkanowy/WulkanowyApp.kt
@@ -6,6 +6,7 @@ import android.util.Log.VERBOSE
 import androidx.multidex.MultiDex
 import androidx.work.Configuration
 import com.jakewharton.threetenabp.AndroidThreeTen
+import com.yariksoffice.lingver.Lingver
 import dagger.android.AndroidInjector
 import dagger.android.support.DaggerApplication
 import eu.davidea.flexibleadapter.FlexibleAdapter
@@ -44,6 +45,7 @@ class WulkanowyApp : DaggerApplication(), Configuration.Provider {
         super.onCreate()
         AndroidThreeTen.init(this)
         RxJavaPlugins.setErrorHandler(::onError)
+        Lingver.init(this)
         themeManager.applyDefaultTheme()
 
         initLogging()
diff --git a/app/src/main/java/io/github/wulkanowy/data/repositories/preferences/PreferencesRepository.kt b/app/src/main/java/io/github/wulkanowy/data/repositories/preferences/PreferencesRepository.kt
index e1caf920..07a3654a 100644
--- a/app/src/main/java/io/github/wulkanowy/data/repositories/preferences/PreferencesRepository.kt
+++ b/app/src/main/java/io/github/wulkanowy/data/repositories/preferences/PreferencesRepository.kt
@@ -33,6 +33,10 @@ class PreferencesRepository @Inject constructor(
     val gradeColorTheme: String
         get() = getString(R.string.pref_key_grade_color_scheme, R.string.pref_default_grade_color_scheme)
 
+    val appLanguageKey = context.getString(R.string.pref_key_app_language)
+    val appLanguage
+        get() = getString(appLanguageKey, R.string.pref_default_app_language)
+
     val serviceEnableKey = context.getString(R.string.pref_key_services_enable)
     val isServiceEnabled: Boolean
         get() = getBoolean(serviceEnableKey, R.bool.pref_default_services_enable)
diff --git a/app/src/main/java/io/github/wulkanowy/di/AppModule.kt b/app/src/main/java/io/github/wulkanowy/di/AppModule.kt
index 42e50fa4..4f568385 100644
--- a/app/src/main/java/io/github/wulkanowy/di/AppModule.kt
+++ b/app/src/main/java/io/github/wulkanowy/di/AppModule.kt
@@ -2,6 +2,7 @@ package io.github.wulkanowy.di
 
 import android.appwidget.AppWidgetManager
 import android.content.Context
+import com.yariksoffice.lingver.Lingver
 import dagger.Module
 import dagger.Provides
 import eu.davidea.flexibleadapter.FlexibleAdapter
@@ -32,4 +33,8 @@ internal class AppModule {
     @Singleton
     @Provides
     fun provideAppInfo() = AppInfo()
+
+    @Singleton
+    @Provides
+    fun provideLingver() = Lingver.getInstance()
 }
diff --git a/app/src/main/java/io/github/wulkanowy/ui/modules/login/form/LoginFormFragment.kt b/app/src/main/java/io/github/wulkanowy/ui/modules/login/form/LoginFormFragment.kt
index 1288e299..8c7b52ea 100644
--- a/app/src/main/java/io/github/wulkanowy/ui/modules/login/form/LoginFormFragment.kt
+++ b/app/src/main/java/io/github/wulkanowy/ui/modules/login/form/LoginFormFragment.kt
@@ -16,7 +16,7 @@ import io.github.wulkanowy.ui.base.BaseFragment
 import io.github.wulkanowy.ui.modules.login.LoginActivity
 import io.github.wulkanowy.utils.AppInfo
 import io.github.wulkanowy.utils.hideSoftInput
-import io.github.wulkanowy.utils.openEmail
+import io.github.wulkanowy.utils.openEmailClient
 import io.github.wulkanowy.utils.openInternetBrowser
 import io.github.wulkanowy.utils.showSoftInput
 import kotlinx.android.synthetic.main.fragment_login_form.*
@@ -166,7 +166,7 @@ class LoginFormFragment : BaseFragment(), LoginFormView {
     }
 
     override fun openEmail() {
-        context?.openEmail(
+        context?.openEmailClient(
             requireContext().getString(R.string.login_email_intent_title),
             "wulkanowyinc@gmail.com",
             requireContext().getString(R.string.login_email_subject),
diff --git a/app/src/main/java/io/github/wulkanowy/ui/modules/login/studentselect/LoginStudentSelectFragment.kt b/app/src/main/java/io/github/wulkanowy/ui/modules/login/studentselect/LoginStudentSelectFragment.kt
index dba0c951..8478f7cc 100644
--- a/app/src/main/java/io/github/wulkanowy/ui/modules/login/studentselect/LoginStudentSelectFragment.kt
+++ b/app/src/main/java/io/github/wulkanowy/ui/modules/login/studentselect/LoginStudentSelectFragment.kt
@@ -14,7 +14,7 @@ import io.github.wulkanowy.data.db.entities.Student
 import io.github.wulkanowy.ui.base.BaseFragment
 import io.github.wulkanowy.ui.modules.main.MainActivity
 import io.github.wulkanowy.utils.AppInfo
-import io.github.wulkanowy.utils.openEmail
+import io.github.wulkanowy.utils.openEmailClient
 import io.github.wulkanowy.utils.openInternetBrowser
 import io.github.wulkanowy.utils.setOnItemClickListener
 import kotlinx.android.synthetic.main.fragment_login_student_select.*
@@ -102,7 +102,7 @@ class LoginStudentSelectFragment : BaseFragment(), LoginStudentSelectView {
     }
 
     override fun openEmail() {
-        context?.openEmail(
+        context?.openEmailClient(
             requireContext().getString(R.string.login_email_intent_title),
             "wulkanowyinc@gmail.com",
             requireContext().getString(R.string.login_email_subject),
diff --git a/app/src/main/java/io/github/wulkanowy/ui/modules/login/symbol/LoginSymbolFragment.kt b/app/src/main/java/io/github/wulkanowy/ui/modules/login/symbol/LoginSymbolFragment.kt
index 724e3fbb..b7ae39a7 100644
--- a/app/src/main/java/io/github/wulkanowy/ui/modules/login/symbol/LoginSymbolFragment.kt
+++ b/app/src/main/java/io/github/wulkanowy/ui/modules/login/symbol/LoginSymbolFragment.kt
@@ -16,7 +16,7 @@ import io.github.wulkanowy.ui.base.BaseFragment
 import io.github.wulkanowy.ui.modules.login.LoginActivity
 import io.github.wulkanowy.utils.AppInfo
 import io.github.wulkanowy.utils.hideSoftInput
-import io.github.wulkanowy.utils.openEmail
+import io.github.wulkanowy.utils.openEmailClient
 import io.github.wulkanowy.utils.openInternetBrowser
 import io.github.wulkanowy.utils.showSoftInput
 import kotlinx.android.synthetic.main.fragment_login_symbol.*
@@ -131,7 +131,7 @@ class LoginSymbolFragment : BaseFragment(), LoginSymbolView {
     }
 
     override fun openEmail() {
-        context?.openEmail(
+        context?.openEmailClient(
             requireContext().getString(R.string.login_email_intent_title),
             "wulkanowyinc@gmail.com",
             requireContext().getString(R.string.login_email_subject),
diff --git a/app/src/main/java/io/github/wulkanowy/ui/modules/schoolandteachers/school/SchoolFragment.kt b/app/src/main/java/io/github/wulkanowy/ui/modules/schoolandteachers/school/SchoolFragment.kt
index 92f74ca8..4e944d38 100644
--- a/app/src/main/java/io/github/wulkanowy/ui/modules/schoolandteachers/school/SchoolFragment.kt
+++ b/app/src/main/java/io/github/wulkanowy/ui/modules/schoolandteachers/school/SchoolFragment.kt
@@ -10,8 +10,8 @@ import io.github.wulkanowy.ui.base.BaseFragment
 import io.github.wulkanowy.ui.modules.main.MainView
 import io.github.wulkanowy.ui.modules.schoolandteachers.SchoolAndTeachersChildView
 import io.github.wulkanowy.ui.modules.schoolandteachers.SchoolAndTeachersFragment
-import io.github.wulkanowy.utils.dialPhone
-import io.github.wulkanowy.utils.openMapLocation
+import io.github.wulkanowy.utils.openDialer
+import io.github.wulkanowy.utils.openNavigation
 import kotlinx.android.synthetic.main.fragment_school.*
 import javax.inject.Inject
 
@@ -86,10 +86,10 @@ class SchoolFragment : BaseFragment(), SchoolView, MainView.TitledView, SchoolAn
     }
 
     override fun openMapsLocation(location: String) {
-        context?.openMapLocation(location)
+        context?.openNavigation(location)
     }
 
     override fun dialPhone(phone: String) {
-        context?.dialPhone(phone)
+        context?.openDialer(phone)
     }
 }
diff --git a/app/src/main/java/io/github/wulkanowy/ui/modules/settings/SettingsFragment.kt b/app/src/main/java/io/github/wulkanowy/ui/modules/settings/SettingsFragment.kt
index cb172b98..17274980 100644
--- a/app/src/main/java/io/github/wulkanowy/ui/modules/settings/SettingsFragment.kt
+++ b/app/src/main/java/io/github/wulkanowy/ui/modules/settings/SettingsFragment.kt
@@ -5,6 +5,7 @@ import android.content.SharedPreferences
 import android.os.Bundle
 import androidx.preference.Preference
 import androidx.preference.PreferenceFragmentCompat
+import com.yariksoffice.lingver.Lingver
 import dagger.android.support.AndroidSupportInjection
 import io.github.wulkanowy.R
 import io.github.wulkanowy.ui.base.BaseActivity
@@ -12,7 +13,8 @@ import io.github.wulkanowy.ui.modules.main.MainView
 import io.github.wulkanowy.utils.AppInfo
 import javax.inject.Inject
 
-class SettingsFragment : PreferenceFragmentCompat(), SharedPreferences.OnSharedPreferenceChangeListener,
+class SettingsFragment : PreferenceFragmentCompat(),
+    SharedPreferences.OnSharedPreferenceChangeListener,
     MainView.TitledView, SettingsView {
 
     @Inject
@@ -21,6 +23,9 @@ class SettingsFragment : PreferenceFragmentCompat(), SharedPreferences.OnSharedP
     @Inject
     lateinit var appInfo: AppInfo
 
+    @Inject
+    lateinit var lingver: Lingver
+
     companion object {
         fun newInstance() = SettingsFragment()
     }
@@ -50,6 +55,10 @@ class SettingsFragment : PreferenceFragmentCompat(), SharedPreferences.OnSharedP
         activity?.recreate()
     }
 
+    override fun updateLanguage(langCode: String) {
+        lingver.setLocale(requireContext(), langCode)
+    }
+
     override fun setServicesSuspended(serviceEnablesKey: String, isHolidays: Boolean) {
         findPreference<Preference>(serviceEnablesKey)?.apply {
             summary = if (isHolidays) getString(R.string.pref_services_suspended) else ""
diff --git a/app/src/main/java/io/github/wulkanowy/ui/modules/settings/SettingsPresenter.kt b/app/src/main/java/io/github/wulkanowy/ui/modules/settings/SettingsPresenter.kt
index 88d38e0d..89ba0ee5 100644
--- a/app/src/main/java/io/github/wulkanowy/ui/modules/settings/SettingsPresenter.kt
+++ b/app/src/main/java/io/github/wulkanowy/ui/modules/settings/SettingsPresenter.kt
@@ -6,6 +6,7 @@ import io.github.wulkanowy.data.repositories.student.StudentRepository
 import io.github.wulkanowy.services.sync.SyncManager
 import io.github.wulkanowy.ui.base.BasePresenter
 import io.github.wulkanowy.ui.base.ErrorHandler
+import io.github.wulkanowy.utils.AppInfo
 import io.github.wulkanowy.utils.FirebaseAnalyticsHelper
 import io.github.wulkanowy.utils.SchedulersProvider
 import io.github.wulkanowy.utils.isHolidays
@@ -20,7 +21,8 @@ class SettingsPresenter @Inject constructor(
     private val preferencesRepository: PreferencesRepository,
     private val analytics: FirebaseAnalyticsHelper,
     private val syncManager: SyncManager,
-    private val chuckCollector: ChuckCollector
+    private val chuckCollector: ChuckCollector,
+    private val appInfo: AppInfo
 ) : BasePresenter<SettingsView>(errorHandler, studentRepository, schedulers) {
 
     override fun onAttachView(view: SettingsView) {
@@ -38,6 +40,10 @@ class SettingsPresenter @Inject constructor(
                 servicesIntervalKey, servicesOnlyWifiKey -> syncManager.startSyncWorker(true)
                 isDebugNotificationEnableKey -> chuckCollector.showNotification(isDebugNotificationEnable)
                 appThemeKey -> view?.recreateView()
+                appLanguageKey -> view?.run {
+                    updateLanguage(if (appLanguage == "system") appInfo.systemLanguage else appLanguage)
+                    recreateView()
+                }
                 else -> Unit
             }
         }
diff --git a/app/src/main/java/io/github/wulkanowy/ui/modules/settings/SettingsView.kt b/app/src/main/java/io/github/wulkanowy/ui/modules/settings/SettingsView.kt
index 1c4bf3b0..e50eb47b 100644
--- a/app/src/main/java/io/github/wulkanowy/ui/modules/settings/SettingsView.kt
+++ b/app/src/main/java/io/github/wulkanowy/ui/modules/settings/SettingsView.kt
@@ -6,5 +6,7 @@ interface SettingsView : BaseView {
 
     fun recreateView()
 
+    fun updateLanguage(langCode: String)
+
     fun setServicesSuspended(serviceEnablesKey: String, isHolidays: Boolean)
 }
diff --git a/app/src/main/java/io/github/wulkanowy/utils/AppInfo.kt b/app/src/main/java/io/github/wulkanowy/utils/AppInfo.kt
index 3fa83a04..a444da6f 100644
--- a/app/src/main/java/io/github/wulkanowy/utils/AppInfo.kt
+++ b/app/src/main/java/io/github/wulkanowy/utils/AppInfo.kt
@@ -1,5 +1,6 @@
 package io.github.wulkanowy.utils
 
+import android.content.res.Resources
 import android.os.Build.MANUFACTURER
 import android.os.Build.MODEL
 import android.os.Build.VERSION.SDK_INT
@@ -25,4 +26,8 @@ open class AppInfo {
     open val systemManufacturer: String get() = MANUFACTURER
 
     open val systemModel: String get() = MODEL
+
+    @Suppress("DEPRECATION")
+    open val systemLanguage: String
+        get() = Resources.getSystem().configuration.locale.language
 }
diff --git a/app/src/main/java/io/github/wulkanowy/utils/ContextExtension.kt b/app/src/main/java/io/github/wulkanowy/utils/ContextExtension.kt
index 5110b067..a265378e 100644
--- a/app/src/main/java/io/github/wulkanowy/utils/ContextExtension.kt
+++ b/app/src/main/java/io/github/wulkanowy/utils/ContextExtension.kt
@@ -32,7 +32,7 @@ fun Context.openInternetBrowser(uri: String, onActivityNotFound: (uri: String) -
     }
 }
 
-fun Context.openEmail(chooserTitle: String, email: String, subject: String?, body: String?) {
+fun Context.openEmailClient(chooserTitle: String, email: String, subject: String?, body: String?) {
     val emailIntent = Intent(Intent.ACTION_SENDTO, Uri.fromParts("mailto", email, null))
     emailIntent.putExtra(Intent.EXTRA_EMAIL, arrayOf(email))
     if (subject != null) emailIntent.putExtra(Intent.EXTRA_SUBJECT, subject)
@@ -40,7 +40,7 @@ fun Context.openEmail(chooserTitle: String, email: String, subject: String?, bod
     startActivity(Intent.createChooser(emailIntent, chooserTitle))
 }
 
-fun Context.openMapLocation(location: String) {
+fun Context.openNavigation(location: String) {
     val intentUri = Uri.parse("geo:0,0?q=${Uri.encode(location)}")
     val intent = Intent(Intent.ACTION_VIEW, intentUri)
     if (intent.resolveActivity(packageManager) != null) {
@@ -48,7 +48,7 @@ fun Context.openMapLocation(location: String) {
     }
 }
 
-fun Context.dialPhone(phone: String) {
+fun Context.openDialer(phone: String) {
     val intentUri = Uri.parse("tel:$phone")
     val intent = Intent(Intent.ACTION_DIAL, intentUri)
     startActivity(intent)
diff --git a/app/src/main/res/values-pl/preferences_values.xml b/app/src/main/res/values-pl/preferences_values.xml
index e4c30eb0..facec3f0 100644
--- a/app/src/main/res/values-pl/preferences_values.xml
+++ b/app/src/main/res/values-pl/preferences_values.xml
@@ -16,6 +16,12 @@
         <item>Czarny (AMOLED)</item>
     </string-array>
 
+    <string-array name="app_language_entries">
+        <item>Język systemu</item>
+        <item>Polski</item>
+        <item>English</item>
+    </string-array>
+
     <string-array name="grade_modifier_entries">
         <item>Domyślna</item>
         <item>0,25</item>
diff --git a/app/src/main/res/values-pl/strings.xml b/app/src/main/res/values-pl/strings.xml
index 8ff4d307..2ceff8a0 100644
--- a/app/src/main/res/values-pl/strings.xml
+++ b/app/src/main/res/values-pl/strings.xml
@@ -300,6 +300,7 @@
     <string name="pref_view_app_theme">Motyw aplikacji</string>
     <string name="pref_view_expand_grade">Rozwiń oceny</string>
     <string name="pref_view_grade_color_scheme">Schemat kolorów ocen</string>
+    <string name="pref_view_app_language">Język aplikacji</string>
 
     <string name="pref_notify_header">Powiadomienia</string>
     <string name="pref_notify_switch">Pokazuj powiadomienia</string>
diff --git a/app/src/main/res/values/preferences_defaults.xml b/app/src/main/res/values/preferences_defaults.xml
index 53b5c2ab..733d71b0 100644
--- a/app/src/main/res/values/preferences_defaults.xml
+++ b/app/src/main/res/values/preferences_defaults.xml
@@ -7,6 +7,7 @@
     <bool name="pref_default_expand_grade">false</bool>
     <string name="pref_default_app_theme">light</string>
     <string name="pref_default_grade_color_scheme">vulcan</string>
+    <string name="pref_default_app_language">system</string>
     <bool name="pref_default_services_enable">true</bool>
     <string name="pref_default_services_interval">60</string>
     <bool name="pref_default_services_wifi_only">false</bool>
diff --git a/app/src/main/res/values/preferences_keys.xml b/app/src/main/res/values/preferences_keys.xml
index 730fea59..a2172db9 100644
--- a/app/src/main/res/values/preferences_keys.xml
+++ b/app/src/main/res/values/preferences_keys.xml
@@ -7,6 +7,7 @@
     <string name="pref_key_expand_grade">expand_grade</string>
     <string name="pref_key_grade_average_mode">grade_average_mode</string>
     <string name="pref_key_grade_average_force_calc">grade_average_always_calc</string>
+    <string name="pref_key_app_language">app_language</string>
     <string name="pref_key_services_enable">services_enable</string>
     <string name="pref_key_services_interval">services_interval</string>
     <string name="pref_key_services_wifi_only">services_disable_wifi_only</string>
diff --git a/app/src/main/res/values/preferences_values.xml b/app/src/main/res/values/preferences_values.xml
index 289f14f3..52de39e1 100644
--- a/app/src/main/res/values/preferences_values.xml
+++ b/app/src/main/res/values/preferences_values.xml
@@ -24,6 +24,17 @@
         <item>black</item>
     </string-array>
 
+    <string-array name="app_language_entries">
+        <item>System language</item>
+        <item>Polski</item>
+        <item>English</item>
+    </string-array>
+    <string-array name="app_language_values" translatable="false">
+        <item>system</item>
+        <item>pl</item>
+        <item>en</item>
+    </string-array>
+
     <string-array name="services_interval_entries">
         <item>15 minutes</item>
         <item>30 minutes</item>
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index 4660f9fe..d5149a1d 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -286,6 +286,7 @@
     <string name="pref_view_app_theme">Application theme</string>
     <string name="pref_view_expand_grade">Expand grades</string>
     <string name="pref_view_grade_color_scheme">Grades color scheme</string>
+    <string name="pref_view_app_language">App language</string>
 
     <string name="pref_notify_header">Notifications</string>
     <string name="pref_notify_switch">Show notifications</string>
diff --git a/app/src/main/res/xml/scheme_preferences.xml b/app/src/main/res/xml/scheme_preferences.xml
index 28229f41..d9e6c533 100644
--- a/app/src/main/res/xml/scheme_preferences.xml
+++ b/app/src/main/res/xml/scheme_preferences.xml
@@ -37,6 +37,14 @@
             app:key="@string/pref_key_grade_color_scheme"
             app:title="@string/pref_view_grade_color_scheme"
             app:useSimpleSummaryProvider="true" />
+        <ListPreference
+            app:defaultValue="@string/pref_default_app_language"
+            app:entries="@array/app_language_entries"
+            app:entryValues="@array/app_language_values"
+            app:iconSpaceReserved="false"
+            app:key="@string/pref_key_app_language"
+            app:title="@string/pref_view_app_language"
+            app:useSimpleSummaryProvider="true" />
     </PreferenceCategory>
     <PreferenceCategory
         app:iconSpaceReserved="false"
@@ -106,9 +114,9 @@
             app:useSimpleSummaryProvider="true" />
         <SwitchPreferenceCompat
             app:defaultValue="@bool/pref_default_grade_average_force_calc"
+            app:iconSpaceReserved="false"
             app:key="@string/pref_key_grade_average_force_calc"
-            app:title="@string/pref_view_grade_average_force_calc"
-            app:iconSpaceReserved="false" />
+            app:title="@string/pref_view_grade_average_force_calc" />
         <SwitchPreferenceCompat
             app:defaultValue="@bool/pref_default_fill_message_content"
             app:iconSpaceReserved="false"