diff --git a/apps/calculation/edit_expression_controller.cpp b/apps/calculation/edit_expression_controller.cpp
index 9f09c8b2d..cdd01e69f 100644
--- a/apps/calculation/edit_expression_controller.cpp
+++ b/apps/calculation/edit_expression_controller.cpp
@@ -82,8 +82,7 @@ bool EditExpressionController::textFieldDidReceiveEvent(::TextField * textField,
 
 bool EditExpressionController::textFieldDidFinishEditing(::TextField * textField, const char * text) {
   App * calculationApp = (App *)app();
-  AppsContainer * appsContainer = (AppsContainer *)calculationApp->container();
-  m_calculationStore->push(textBody(), calculationApp->localContext(), appsContainer->preferences());
+  m_calculationStore->push(textBody(), calculationApp->localContext(), calculationApp->container()->preferences());
   m_historyController->reload();
   m_contentView.mainView()->scrollToCell(0, m_historyController->numberOfRows()-1);
   m_contentView.textField()->setText("");
diff --git a/apps/calculation/history_controller.cpp b/apps/calculation/history_controller.cpp
index fd986e0ce..567738137 100644
--- a/apps/calculation/history_controller.cpp
+++ b/apps/calculation/history_controller.cpp
@@ -71,8 +71,7 @@ bool HistoryController::handleEvent(Ion::Events::Event event) {
     }
     m_selectableTableView.deselectTable();
     App * calculationApp = (App *)app();
-    AppsContainer * appsContainer = (AppsContainer *)calculationApp->container();
-    m_calculationStore->push(text, calculationApp->localContext(), appsContainer->preferences());
+    m_calculationStore->push(text, calculationApp->localContext(), calculationApp->container()->preferences());
     reload();
     m_selectableTableView.scrollToCell(0, numberOfRows()-1);
     app()->setFirstResponder(editController);
diff --git a/apps/graph/graph/goto_parameter_controller.cpp b/apps/graph/graph/goto_parameter_controller.cpp
index bcc5657ad..e488f218a 100644
--- a/apps/graph/graph/goto_parameter_controller.cpp
+++ b/apps/graph/graph/goto_parameter_controller.cpp
@@ -28,8 +28,7 @@ float GoToParameterController::parameterAtIndex(int index) {
 void GoToParameterController::setParameterAtIndex(int parameterIndex, float f) {
   assert(parameterIndex == 0);
   App * graphApp = (Graph::App *)app();
-  AppsContainer * container = (AppsContainer *)graphApp->container();
-  float y = m_function->evaluateAtAbscissa(f, graphApp->localContext(), container->preferences()->angleUnit());
+  float y = m_function->evaluateAtAbscissa(f, graphApp->localContext(), graphApp->container()->preferences()->angleUnit());
   m_graphRange->centerAxisAround(CurveViewRange::Axis::X, f);
   m_graphRange->centerAxisAround(CurveViewRange::Axis::Y, y);
   m_cursor->moveTo(f, y);
diff --git a/apps/graph/graph/graph_controller.cpp b/apps/graph/graph/graph_controller.cpp
index 930c3b9df..1b25de9df 100644
--- a/apps/graph/graph/graph_controller.cpp
+++ b/apps/graph/graph/graph_controller.cpp
@@ -44,8 +44,7 @@ void GraphController::didBecomeFirstResponder() {
   if (m_view.context() == nullptr) {
     App * graphApp = (Graph::App *)app();
     m_view.setContext(graphApp->localContext());
-    AppsContainer * container = (AppsContainer *)graphApp->container();
-    m_view.setPreferences(container->preferences());
+    m_view.setPreferences(graphApp->container()->preferences());
   }
   InteractiveCurveViewController::didBecomeFirstResponder();
 }
@@ -55,7 +54,6 @@ bool GraphController::didChangeRange(InteractiveCurveViewRange * interactiveCurv
     return false;
   }
   App * graphApp = (Graph::App *)app();
-  AppsContainer * myContainer = (AppsContainer *)graphApp->container();
   if (m_functionStore->numberOfActiveFunctions() <= 0) {
     return false;
   }
@@ -69,7 +67,7 @@ bool GraphController::didChangeRange(InteractiveCurveViewRange * interactiveCurv
     float y = 0.0f;
     for (int i = 0; i <= Ion::Display::Width; i++) {
       float x = xMin + i*step;
-      y = f->evaluateAtAbscissa(x, graphApp->localContext(), myContainer->preferences()->angleUnit());
+      y = f->evaluateAtAbscissa(x, graphApp->localContext(), graphApp->container()->preferences()->angleUnit());
       if (!isnan(y) && !isinf(y)) {
         min = min < y ? min : y;
         max = max > y ? max : y;
@@ -113,13 +111,12 @@ bool GraphController::handleEnter() {
 }
 
 void GraphController::reloadBannerView() {
-  App * myApp = (App *)app();
-  AppsContainer * myContainer = (AppsContainer *)myApp->container();
+  App * graphApp = (App *)app();
   char buffer[k_maxNumberOfCharacters+Complex::bufferSizeForFloatsWithPrecision(Constant::LargeNumberOfSignificantDigits)];
   const char * legend = "x = ";
   int legendLength = strlen(legend);
   strlcpy(buffer, legend, legendLength+1);
-  Complex::convertFloatToText(m_cursor.x(), buffer+ legendLength, Complex::bufferSizeForFloatsWithPrecision(Constant::LargeNumberOfSignificantDigits), Constant::LargeNumberOfSignificantDigits, myContainer->preferences()->displayMode());
+  Complex::convertFloatToText(m_cursor.x(), buffer+ legendLength, Complex::bufferSizeForFloatsWithPrecision(Constant::LargeNumberOfSignificantDigits), Constant::LargeNumberOfSignificantDigits, graphApp->container()->preferences()->displayMode());
   m_bannerView.setLegendAtIndex(buffer, 0);
 
   legend = "00(x) = ";
@@ -127,15 +124,15 @@ void GraphController::reloadBannerView() {
   strlcpy(buffer, legend, legendLength+1);
   Function * f = m_functionStore->activeFunctionAtIndex(m_indexFunctionSelectedByCursor);
   buffer[1] = f->name()[0];
-  Complex::convertFloatToText(m_cursor.y(), buffer+legendLength, Complex::bufferSizeForFloatsWithPrecision(Constant::LargeNumberOfSignificantDigits), Constant::LargeNumberOfSignificantDigits, myContainer->preferences()->displayMode());
+  Complex::convertFloatToText(m_cursor.y(), buffer+legendLength, Complex::bufferSizeForFloatsWithPrecision(Constant::LargeNumberOfSignificantDigits), Constant::LargeNumberOfSignificantDigits, graphApp->container()->preferences()->displayMode());
   m_bannerView.setLegendAtIndex(buffer+1, 1);
 
   if (m_bannerView.displayDerivative()) {
     buffer[0] = f->name()[0];
     buffer[1] = '\'';
     App * graphApp = (Graph::App *)app();
-    float y = f->approximateDerivative(m_cursor.x(), graphApp->localContext(), myContainer->preferences()->angleUnit());
-    Complex::convertFloatToText(y, buffer + legendLength, Complex::bufferSizeForFloatsWithPrecision(Constant::LargeNumberOfSignificantDigits), Constant::LargeNumberOfSignificantDigits, myContainer->preferences()->displayMode());
+    float y = f->approximateDerivative(m_cursor.x(), graphApp->localContext(), graphApp->container()->preferences()->angleUnit());
+    Complex::convertFloatToText(y, buffer + legendLength, Complex::bufferSizeForFloatsWithPrecision(Constant::LargeNumberOfSignificantDigits), Constant::LargeNumberOfSignificantDigits, graphApp->container()->preferences()->displayMode());
     m_bannerView.setLegendAtIndex(buffer, 2);
   }
 }
@@ -150,12 +147,11 @@ void GraphController::initCursorParameters() {
   float x = (m_graphRange.xMin()+m_graphRange.xMax())/2.0f;
   m_indexFunctionSelectedByCursor = 0;
   App * graphApp = (Graph::App *)app();
-  AppsContainer * myContainer = (AppsContainer *)graphApp->container();
   int functionIndex = 0;
   float y = 0;
   do {
     Function * firstFunction = m_functionStore->activeFunctionAtIndex(functionIndex++);
-    y = firstFunction->evaluateAtAbscissa(x, graphApp->localContext(), myContainer->preferences()->angleUnit());
+    y = firstFunction->evaluateAtAbscissa(x, graphApp->localContext(), graphApp->container()->preferences()->angleUnit());
   } while (isnan(y) && functionIndex < m_functionStore->numberOfActiveFunctions());
   m_cursor.moveTo(x, y);
   m_graphRange.panToMakePointVisible(x, y, k_cursorTopMarginRatio, k_cursorRightMarginRatio, k_cursorBottomMarginRatio, k_cursorLeftMarginRatio);
@@ -167,8 +163,7 @@ bool GraphController::moveCursorHorizontally(int direction) {
     xCursorPosition -  m_graphRange.xGridUnit()/k_numberOfCursorStepsInGradUnit;
   Function * f = m_functionStore->activeFunctionAtIndex(m_indexFunctionSelectedByCursor);
   App * graphApp = (Graph::App *)app();
-  AppsContainer * myContainer = (AppsContainer *)graphApp->container();
-  float y = f->evaluateAtAbscissa(x, graphApp->localContext(), myContainer->preferences()->angleUnit());
+  float y = f->evaluateAtAbscissa(x, graphApp->localContext(), graphApp->container()->preferences()->angleUnit());
   m_cursor.moveTo(x, y);
   m_graphRange.panToMakePointVisible(x, y, k_cursorTopMarginRatio, k_cursorRightMarginRatio, k_cursorBottomMarginRatio, k_cursorLeftMarginRatio);
   return true;
@@ -177,13 +172,12 @@ bool GraphController::moveCursorHorizontally(int direction) {
 bool GraphController::moveCursorVertically(int direction) {
   Function * actualFunction = m_functionStore->activeFunctionAtIndex(m_indexFunctionSelectedByCursor);
   App * graphApp = (Graph::App *)app();
-  AppsContainer * myContainer = (AppsContainer *)graphApp->container();
-  float y = actualFunction->evaluateAtAbscissa(m_cursor.x(), graphApp->localContext(), myContainer->preferences()->angleUnit());
+  float y = actualFunction->evaluateAtAbscissa(m_cursor.x(), graphApp->localContext(), graphApp->container()->preferences()->angleUnit());
   Function * nextFunction = actualFunction;
   float nextY = direction > 0 ? FLT_MAX : -FLT_MAX;
   for (int i = 0; i < m_functionStore->numberOfActiveFunctions(); i++) {
     Function * f = m_functionStore->activeFunctionAtIndex(i);
-    float newY = f->evaluateAtAbscissa(m_cursor.x(), graphApp->localContext(), myContainer->preferences()->angleUnit());
+    float newY = f->evaluateAtAbscissa(m_cursor.x(), graphApp->localContext(), graphApp->container()->preferences()->angleUnit());
     bool isNextFunction = direction > 0 ? (newY > y && newY < nextY) : (newY < y && newY > nextY);
     if (isNextFunction) {
       m_indexFunctionSelectedByCursor = i;
diff --git a/apps/graph/graph/initialisation_parameter_controller.cpp b/apps/graph/graph/initialisation_parameter_controller.cpp
index 76f6f9bf1..9a0556520 100644
--- a/apps/graph/graph/initialisation_parameter_controller.cpp
+++ b/apps/graph/graph/initialisation_parameter_controller.cpp
@@ -1,4 +1,5 @@
 #include "initialisation_parameter_controller.h"
+#include "../app.h"
 #include "../../apps_container.h"
 #include <assert.h>
 #include <math.h>
@@ -31,8 +32,8 @@ void InitialisationParameterController::didBecomeFirstResponder() {
 bool InitialisationParameterController::handleEvent(Ion::Events::Event event) {
   if (event == Ion::Events::OK) {
     if (m_selectableTableView.selectedRow() == 0) {
-      AppsContainer * container = (AppsContainer *)app()->container();
-      m_graphRange->setTrigonometric(container->preferences()->angleUnit());
+      App * graphApp = (App *)app();
+      m_graphRange->setTrigonometric(graphApp->container()->preferences()->angleUnit());
     } else {
       RangeMethodPointer rangeMethods[k_totalNumberOfCells-1] = {&InteractiveCurveViewRange::roundAbscissa,
         &InteractiveCurveViewRange::normalize, &InteractiveCurveViewRange::setDefault};
diff --git a/apps/graph/values/values_controller.cpp b/apps/graph/values/values_controller.cpp
index 7bc7da8cb..32ef229c4 100644
--- a/apps/graph/values/values_controller.cpp
+++ b/apps/graph/values/values_controller.cpp
@@ -40,8 +40,8 @@ const char * ValuesController::title() const {
 }
 
 View * ValuesController::view() {
-  AppsContainer * myContainer = (AppsContainer *)app()->container();
-  Expression::DisplayMode displayMode = myContainer->preferences()->displayMode();
+  App * graphApp = (App *)app();
+  Expression::DisplayMode displayMode = graphApp->container()->preferences()->displayMode();
   if (displayMode != m_displayModeVersion) {
     m_selectableTableView.reloadData();
     m_displayModeVersion = displayMode;
@@ -136,8 +136,8 @@ int ValuesController::numberOfColumns() {
 }
 
 void ValuesController::willDisplayCellAtLocation(TableViewCell * cell, int i, int j) {
-  AppsContainer * myContainer = (AppsContainer *)app()->container();
-  willDisplayCellAtLocationWithDisplayMode(cell, i, j, myContainer->preferences()->displayMode());
+  App * graphApp = (App *)app();
+  willDisplayCellAtLocationWithDisplayMode(cell, i, j, graphApp->container()->preferences()->displayMode());
   if (cellAtLocationIsEditable(i, j)) {
     return;
   }
@@ -179,12 +179,11 @@ void ValuesController::willDisplayCellAtLocation(TableViewCell * cell, int i, in
   // The cell is a value cell
   EvenOddBufferTextCell * myValueCell = (EvenOddBufferTextCell *)cell;
   Function * function = functionAtColumn(i);
-  App * graphApp = (Graph::App *)app();
   float x = m_interval.element(j-1);
   if (isDerivativeColumn(i)) {
-    Complex::convertFloatToText(function->approximateDerivative(x, graphApp->localContext(), myContainer->preferences()->angleUnit()), buffer, Complex::bufferSizeForFloatsWithPrecision(Constant::LargeNumberOfSignificantDigits), Constant::LargeNumberOfSignificantDigits, myContainer->preferences()->displayMode());
+    Complex::convertFloatToText(function->approximateDerivative(x, graphApp->localContext(), graphApp->container()->preferences()->angleUnit()), buffer, Complex::bufferSizeForFloatsWithPrecision(Constant::LargeNumberOfSignificantDigits), Constant::LargeNumberOfSignificantDigits, graphApp->container()->preferences()->displayMode());
   } else {
-    Complex::convertFloatToText(function->evaluateAtAbscissa(x, graphApp->localContext(), myContainer->preferences()->angleUnit()), buffer, Complex::bufferSizeForFloatsWithPrecision(Constant::LargeNumberOfSignificantDigits), Constant::LargeNumberOfSignificantDigits, myContainer->preferences()->displayMode());
+    Complex::convertFloatToText(function->evaluateAtAbscissa(x, graphApp->localContext(), graphApp->container()->preferences()->angleUnit()), buffer, Complex::bufferSizeForFloatsWithPrecision(Constant::LargeNumberOfSignificantDigits), Constant::LargeNumberOfSignificantDigits, graphApp->container()->preferences()->displayMode());
   }
   myValueCell->setText(buffer);
 }
diff --git a/apps/probability/calculation_controller.cpp b/apps/probability/calculation_controller.cpp
index 0367da281..5983e80c0 100644
--- a/apps/probability/calculation_controller.cpp
+++ b/apps/probability/calculation_controller.cpp
@@ -204,9 +204,9 @@ bool CalculationController::textFieldDidReceiveEvent(TextField * textField, Ion:
 }
 
 bool CalculationController::textFieldDidFinishEditing(TextField * textField, const char * text) {
-  AppsContainer * appsContainer = (AppsContainer *)app()->container();
-  Context * globalContext = appsContainer->globalContext();
-  float floatBody = Expression::parse(text)->approximate(*globalContext, appsContainer->preferences()->angleUnit());
+  App * probaApp = (App *)app();
+  Context * globalContext = probaApp->container()->globalContext();
+  float floatBody = Expression::parse(text)->approximate(*globalContext, probaApp->container()->preferences()->angleUnit());
   m_calculation->setParameterAtIndex(floatBody, m_highlightedSubviewIndex-1);
   for (int k = 0; k < m_calculation->numberOfParameters(); k++) {
     m_contentView.willDisplayEditableCellAtIndex(k);
diff --git a/apps/regression/calculation_controller.cpp b/apps/regression/calculation_controller.cpp
index 6e3784a21..9237c3a3a 100644
--- a/apps/regression/calculation_controller.cpp
+++ b/apps/regression/calculation_controller.cpp
@@ -127,7 +127,7 @@ void CalculationController::willDisplayCellAtLocation(TableViewCell * cell, int
     myCell->setText(titles[j-1]);
     return;
   }
-  AppsContainer * container = (AppsContainer *)app()->container();
+  App * regApp = (App *)app();
   if (i == 1 && j > 0 && j < 6) {
     ArgCalculPointer calculationMethods[(k_totalNumberOfRows-1)/2] = {&Store::meanOfColumn, &Store::sumOfColumn,
       &Store::squaredValueSumOfColumn, &Store::standardDeviationOfColumn, &Store::varianceOfColumn};
@@ -135,9 +135,9 @@ void CalculationController::willDisplayCellAtLocation(TableViewCell * cell, int
     float calculation2 = (m_store->*calculationMethods[j-1])(1);
     EvenOddDoubleBufferTextCell * myCell = (EvenOddDoubleBufferTextCell *)cell;
     char buffer[Complex::bufferSizeForFloatsWithPrecision(Constant::LargeNumberOfSignificantDigits)];
-    Complex::convertFloatToText(calculation1, buffer, Complex::bufferSizeForFloatsWithPrecision(Constant::LargeNumberOfSignificantDigits), Constant::LargeNumberOfSignificantDigits, container->preferences()->displayMode());
+    Complex::convertFloatToText(calculation1, buffer, Complex::bufferSizeForFloatsWithPrecision(Constant::LargeNumberOfSignificantDigits), Constant::LargeNumberOfSignificantDigits, regApp->container()->preferences()->displayMode());
     myCell->setFirstText(buffer);
-    Complex::convertFloatToText(calculation2, buffer, Complex::bufferSizeForFloatsWithPrecision(Constant::LargeNumberOfSignificantDigits), Constant::LargeNumberOfSignificantDigits, container->preferences()->displayMode());
+    Complex::convertFloatToText(calculation2, buffer, Complex::bufferSizeForFloatsWithPrecision(Constant::LargeNumberOfSignificantDigits), Constant::LargeNumberOfSignificantDigits, regApp->container()->preferences()->displayMode());
     myCell->setSecondText(buffer);
     return;
   }
@@ -147,7 +147,7 @@ void CalculationController::willDisplayCellAtLocation(TableViewCell * cell, int
     float calculation = (m_store->*calculationMethods[j-6])();
     EvenOddBufferTextCell * myCell = (EvenOddBufferTextCell *)cell;
     char buffer[Complex::bufferSizeForFloatsWithPrecision(Constant::LargeNumberOfSignificantDigits)];
-    Complex::convertFloatToText(calculation, buffer, Complex::bufferSizeForFloatsWithPrecision(Constant::LargeNumberOfSignificantDigits), Constant::LargeNumberOfSignificantDigits, container->preferences()->displayMode());
+    Complex::convertFloatToText(calculation, buffer, Complex::bufferSizeForFloatsWithPrecision(Constant::LargeNumberOfSignificantDigits), Constant::LargeNumberOfSignificantDigits, regApp->container()->preferences()->displayMode());
     myCell->setText(buffer);
     return;
   }
diff --git a/apps/regression/graph_controller.cpp b/apps/regression/graph_controller.cpp
index 4bc84da37..13e6eaf8d 100644
--- a/apps/regression/graph_controller.cpp
+++ b/apps/regression/graph_controller.cpp
@@ -57,7 +57,7 @@ bool GraphController::handleEnter() {
 }
 
 void GraphController::reloadBannerView() {
-  AppsContainer * container = (AppsContainer *)app()->container();
+  AppsContainer * container = ((App *)app())->container();
   m_bannerView.setLegendAtIndex((char *)"y = ax+b", 0);
   char buffer[k_maxNumberOfCharacters + Complex::bufferSizeForFloatsWithPrecision(Constant::LargeNumberOfSignificantDigits)];
   const char * legend = "a = ";
diff --git a/apps/shared/editable_cell_table_view_controller.cpp b/apps/shared/editable_cell_table_view_controller.cpp
index 77b0fbd2f..165aa7b09 100644
--- a/apps/shared/editable_cell_table_view_controller.cpp
+++ b/apps/shared/editable_cell_table_view_controller.cpp
@@ -25,7 +25,7 @@ bool EditableCellTableViewController::textFieldDidReceiveEvent(TextField * textF
 }
 
 bool EditableCellTableViewController::textFieldDidFinishEditing(TextField * textField, const char * text) {
-  AppsContainer * appsContainer = (AppsContainer *)app()->container();
+  AppsContainer * appsContainer = ((TextFieldDelegateApp *)app())->container();
   Context * globalContext = appsContainer->globalContext();
   float floatBody = Expression::parse(text)->approximate(*globalContext, appsContainer->preferences()->angleUnit());
   setDataAtLocation(floatBody, m_selectableTableView.selectedColumn(), m_selectableTableView.selectedRow());
diff --git a/apps/shared/float_parameter_controller.cpp b/apps/shared/float_parameter_controller.cpp
index c5f60fc19..47723eb92 100644
--- a/apps/shared/float_parameter_controller.cpp
+++ b/apps/shared/float_parameter_controller.cpp
@@ -36,7 +36,7 @@ void FloatParameterController::willDisplayCellForIndex(TableViewCell * cell, int
 }
 
 bool FloatParameterController::textFieldDidFinishEditing(TextField * textField, const char * text) {
-  AppsContainer * appsContainer = (AppsContainer *)app()->container();
+  AppsContainer * appsContainer = ((TextFieldDelegateApp *)app())->container();
   Context * globalContext = appsContainer->globalContext();
   float floatBody = Expression::parse(text)->approximate(*globalContext, appsContainer->preferences()->angleUnit());
   setParameterAtIndex(m_selectableTableView.selectedRow(), floatBody);
diff --git a/apps/shared/interactive_curve_view_controller.cpp b/apps/shared/interactive_curve_view_controller.cpp
index 8397e51a0..4c009091d 100644
--- a/apps/shared/interactive_curve_view_controller.cpp
+++ b/apps/shared/interactive_curve_view_controller.cpp
@@ -1,4 +1,5 @@
 #include "interactive_curve_view_controller.h"
+#include "text_field_delegate_app.h"
 #include "../apps_container.h"
 #include <assert.h>
 #include <math.h>
@@ -38,7 +39,7 @@ const char * InteractiveCurveViewController::title() const {
 }
 
 View * InteractiveCurveViewController::view() {
-  AppsContainer * myContainer = (AppsContainer *)app()->container();
+  AppsContainer * myContainer = ((TextFieldDelegateApp *)app())->container();
   Expression::DisplayMode displayMode = myContainer->preferences()->displayMode();
   if (displayMode != m_displayModeVersion) {
     reloadBannerView();
diff --git a/apps/shared/range_parameter_controller.cpp b/apps/shared/range_parameter_controller.cpp
index 3c757f2c6..31a196361 100644
--- a/apps/shared/range_parameter_controller.cpp
+++ b/apps/shared/range_parameter_controller.cpp
@@ -1,4 +1,5 @@
 #include "range_parameter_controller.h"
+#include "text_field_delegate_app.h"
 #include "../apps_container.h"
 #include <assert.h>
 
@@ -36,7 +37,7 @@ void RangeParameterController::willDisplayCellForIndex(TableViewCell * cell, int
 }
 
 bool RangeParameterController::textFieldDidFinishEditing(TextField * textField, const char * text) {
-  AppsContainer * appsContainer = (AppsContainer *)app()->container();
+  AppsContainer * appsContainer = ((TextFieldDelegateApp *)app())->container();
   Context * globalContext = appsContainer->globalContext();
   float floatBody = Expression::parse(text)->approximate(*globalContext, appsContainer->preferences()->angleUnit());
   setParameterAtIndex(m_selectableTableView.selectedRow(), floatBody);
diff --git a/apps/shared/text_field_delegate_app.cpp b/apps/shared/text_field_delegate_app.cpp
index d072bc905..bca6eab07 100644
--- a/apps/shared/text_field_delegate_app.cpp
+++ b/apps/shared/text_field_delegate_app.cpp
@@ -13,8 +13,11 @@ TextFieldDelegateApp::TextFieldDelegateApp(Container * container, ViewController
 }
 
 Context * TextFieldDelegateApp::localContext() {
-  AppsContainer * appsContainer = (AppsContainer *)app()->container();
-  return appsContainer->globalContext();
+  return container()->globalContext();
+}
+
+AppsContainer * TextFieldDelegateApp::container() {
+  return (AppsContainer *)app()->container();
 }
 
 }
diff --git a/apps/shared/text_field_delegate_app.h b/apps/shared/text_field_delegate_app.h
index a15f45b1f..9d2783b49 100644
--- a/apps/shared/text_field_delegate_app.h
+++ b/apps/shared/text_field_delegate_app.h
@@ -4,12 +4,15 @@
 #include <escher.h>
 #include "expression_text_field_delegate.h"
 
+class AppsContainer;
+
 namespace Shared {
 
 class TextFieldDelegateApp : public ::App, public ExpressionTextFieldDelegate {
 public:
   TextFieldDelegateApp(Container * container, ViewController * rootViewController, const char * name = nullptr, const char * upperName = nullptr, const Image * icon = nullptr);
   virtual Poincare::Context * localContext() override;
+  AppsContainer * container();
 };
 
 }
diff --git a/apps/statistics/box_controller.cpp b/apps/statistics/box_controller.cpp
index 346db09ca..648572d93 100644
--- a/apps/statistics/box_controller.cpp
+++ b/apps/statistics/box_controller.cpp
@@ -1,5 +1,6 @@
 #include "box_controller.h"
 #include "../apps_container.h"
+#include "app.h"
 #include <math.h>
 
 using namespace Poincare;
@@ -21,7 +22,7 @@ const char * BoxController::title() const {
 }
 
 View * BoxController::view() {
-  AppsContainer * myContainer = (AppsContainer *)app()->container();
+  AppsContainer * myContainer = ((App *)app())->container();
   Expression::DisplayMode displayMode = myContainer->preferences()->displayMode();
   if (displayMode != m_displayModeVersion) {
     reloadBannerView();
@@ -79,7 +80,7 @@ void BoxController::reloadBannerView() {
   CalculPointer calculationMethods[5] = {&Store::minValue, &Store::firstQuartile, &Store::median, &Store::thirdQuartile,
     &Store::maxValue};
   float calculation = (m_store->*calculationMethods[(int)m_view.selectedQuantile()])();
-  AppsContainer * container = (AppsContainer *)app()->container();
+  AppsContainer * container = ((App *)app())->container();
   Complex::convertFloatToText(calculation, buffer, Complex::bufferSizeForFloatsWithPrecision(Constant::LargeNumberOfSignificantDigits), Constant::LargeNumberOfSignificantDigits, container->preferences()->displayMode());
   m_boxBannerView.setLegendAtIndex(buffer, 1);
 }
diff --git a/apps/statistics/calculation_controller.cpp b/apps/statistics/calculation_controller.cpp
index 8199e4e46..e2e9efe9c 100644
--- a/apps/statistics/calculation_controller.cpp
+++ b/apps/statistics/calculation_controller.cpp
@@ -1,6 +1,7 @@
 #include "calculation_controller.h"
 #include "../constant.h"
 #include "../apps_container.h"
+#include "app.h"
 #include <poincare.h>
 #include <assert.h>
 
@@ -90,7 +91,7 @@ void CalculationController::willDisplayCellAtLocation(TableViewCell * cell, int
     float calculation = (m_store->*calculationMethods[j])();
     EvenOddBufferTextCell * myCell = (EvenOddBufferTextCell *)cell;
     char buffer[Complex::bufferSizeForFloatsWithPrecision(Constant::LargeNumberOfSignificantDigits)];
-    AppsContainer * container = (AppsContainer *)app()->container();
+    AppsContainer * container = ((App *)app())->container();
     Complex::convertFloatToText(calculation, buffer, Complex::bufferSizeForFloatsWithPrecision(Constant::LargeNumberOfSignificantDigits), Constant::LargeNumberOfSignificantDigits, container->preferences()->displayMode());
     myCell->setText(buffer);
   }
diff --git a/apps/statistics/histogram_controller.cpp b/apps/statistics/histogram_controller.cpp
index 093fa1709..ac3d36698 100644
--- a/apps/statistics/histogram_controller.cpp
+++ b/apps/statistics/histogram_controller.cpp
@@ -1,5 +1,6 @@
 #include "histogram_controller.h"
 #include "../apps_container.h"
+#include "app.h"
 #include <assert.h>
 #include <math.h>
 #include <float.h>
@@ -31,8 +32,8 @@ const char * HistogramController::title() const {
 }
 
 View * HistogramController::view() {
-  AppsContainer * myContainer = (AppsContainer *)app()->container();
-  Expression::DisplayMode displayMode = myContainer->preferences()->displayMode();
+  AppsContainer * container = ((App *)app())->container();
+  Expression::DisplayMode displayMode = container->preferences()->displayMode();
   if (displayMode != m_displayModeVersion) {
     reloadBannerView();
     m_view.reload();
@@ -135,7 +136,7 @@ Responder * HistogramController::tabController() const {
 }
 
 void HistogramController::reloadBannerView() {
-  AppsContainer * container = (AppsContainer *)app()->container();
+  AppsContainer * container = ((App *)app())->container();
   char buffer[k_maxNumberOfCharacters+ Complex::bufferSizeForFloatsWithPrecision(Constant::LargeNumberOfSignificantDigits)*2];
   const char * legend = "Interval [";
   int legendLength = strlen(legend);