diff --git a/src/app/app_module.cpp b/src/app/app_module.cpp
index 602d6767..abc58978 100644
--- a/src/app/app_module.cpp
+++ b/src/app/app_module.cpp
@@ -82,7 +82,8 @@ QuantityLength shapeChordalDeflection(const TopoDS_Shape& shape)
 } // namespace
 
 AppModule::AppModule()
-    : m_settings(new Settings),
+    : m_application(new Application),
+      m_settings(new Settings),
       m_props(m_settings),
       m_stdLocale(std::locale("")),
       m_qtLocale(QLocale::system())
@@ -94,6 +95,7 @@ AppModule::AppModule()
     }
 
     m_settings->setPropertyValueConversion(this);
+    Application::defineMayoFormat(m_application);
 }
 
 QStringUtils::TextOptions AppModule::defaultTextOptions() const
diff --git a/src/app/app_module.h b/src/app/app_module.h
index 2fc4c1b8..56a57fbe 100644
--- a/src/app/app_module.h
+++ b/src/app/app_module.h
@@ -9,6 +9,7 @@
 #include "app_module_properties.h"
 #include "qstring_utils.h"
 
+#include "../base/application.h"
 #include "../base/document_tree_node_properties_provider.h"
 #include "../base/io_parameters_provider.h"
 #include "../base/io_system.h"
@@ -53,6 +54,9 @@ class AppModule :
 
     ~AppModule();
 
+    // Application object
+    const ApplicationPtr& application() const { return m_application; }
+
     // Settings
     const AppModuleProperties* properties() const { return &m_props; }
     AppModuleProperties* properties() { return &m_props; }
@@ -121,6 +125,7 @@ class AppModule :
 
     bool impl_recordRecentFile(RecentFile* recentFile, GuiDocument* guiDoc);
 
+    ApplicationPtr m_application;
     Settings* m_settings = nullptr;
     IO::System m_ioSystem;
     AppModuleProperties m_props;
diff --git a/src/app/commands_file.cpp b/src/app/commands_file.cpp
index 8c9d00b8..e382774c 100644
--- a/src/app/commands_file.cpp
+++ b/src/app/commands_file.cpp
@@ -229,7 +229,7 @@ void FileCommandTools::importInDocument(
         QElapsedTimer chrono;
         chrono.start();
 
-        auto doc = Application::instance()->findDocumentByIdentifier(targetDocId);
+        auto doc = appModule->application()->findDocumentByIdentifier(targetDocId);
         const bool okImport = appModule->ioSystem()->importInDocument()
                                   .targetDocument(doc)
                                   .withFilepaths(listFilePaths)
diff --git a/src/app/main.cpp b/src/app/main.cpp
index c06e0ce2..450f90af 100644
--- a/src/app/main.cpp
+++ b/src/app/main.cpp
@@ -368,9 +368,11 @@ static int runApp(QCoreApplication* qtApp)
     }
 
     // Initialize Base application
-    auto app = Application::instance().get();
-    app->addTranslator(&qtAppTranslate); // Set Qt i18n backend
+    auto app = appModule->application();
+    TextId::addTranslatorFunction(&qtAppTranslate); // Set Qt i18n backend
+#ifdef MAYO_OS_WINDOWS
     initOpenCascadeEnvironment("opencascade.conf");
+#endif
 
     // Initialize Gui application
     auto guiApp = new GuiApplication(app);
diff --git a/src/base/application.cpp b/src/base/application.cpp
index ab953787..bf82e5f4 100644
--- a/src/base/application.cpp
+++ b/src/base/application.cpp
@@ -12,7 +12,6 @@
 
 #include <BinXCAFDrivers_DocumentRetrievalDriver.hxx>
 #include <BinXCAFDrivers_DocumentStorageDriver.hxx>
-#include <XCAFApp_Application.hxx>
 #include <XmlXCAFDrivers_DocumentRetrievalDriver.hxx>
 #include <XmlXCAFDrivers_DocumentStorageDriver.hxx>
 #if OCC_VERSION_HEX < OCC_VERSION_CHECK(7, 5, 0)
@@ -20,7 +19,6 @@
 #endif
 
 #include <atomic>
-#include <vector>
 #include <unordered_map>
 
 namespace Mayo {
@@ -52,37 +50,20 @@ class Document::FormatXmlRetrievalDriver : public XmlXCAFDrivers_DocumentRetriev
 struct Application::Private {
     std::atomic<Document::Identifier> m_seqDocumentIdentifier = {};
     std::unordered_map<Document::Identifier, DocumentPtr> m_mapIdentifierDocument;
-    std::vector<Application::Translator> m_vecTranslator;
 };
 
 struct ApplicationI18N {
     MAYO_DECLARE_TEXT_ID_FUNCTIONS(Mayo::Application)
 };
 
-Application::~Application()
+Application::Application()
+    : d(new Private)
 {
-    delete d;
 }
 
-const ApplicationPtr& Application::instance()
+Application::~Application()
 {
-    static ApplicationPtr appPtr;
-    if (!appPtr) {
-        appPtr = new Application;
-        const char strFougueCopyright[] = "Copyright (c) 2021, Fougue Ltd. <http://www.fougue.pro>";
-        appPtr->DefineFormat(
-                    Document::NameFormatBinary, ApplicationI18N::textIdTr("Binary Mayo Document Format").data(), "myb",
-                    new Document::FormatBinaryRetrievalDriver(appPtr),
-                    new BinXCAFDrivers_DocumentStorageDriver
-        );
-        appPtr->DefineFormat(
-                    Document::NameFormatXml, ApplicationI18N::textIdTr("XML Mayo Document Format").data(), "myx",
-                    new Document::FormatXmlRetrievalDriver(appPtr),
-                    new XmlXCAFDrivers_DocumentStorageDriver(strFougueCopyright)
-        );
-    }
-
-    return appPtr;
+    delete d;
 }
 
 int Application::documentCount() const
@@ -117,7 +98,7 @@ DocumentPtr Application::openDocument(const FilePath& filepath, PCDM_ReaderStatu
 DocumentPtr Application::findDocumentByIndex(int docIndex) const
 {
     OccHandle<TDocStd_Document> doc;
-    TDocStd_Application::GetDocument(docIndex + 1, doc);
+    XCAFApp_Application::GetDocument(docIndex + 1, doc);
     return !doc.IsNull() ? DocumentPtr::DownCast(doc) : DocumentPtr();
 }
 
@@ -150,7 +131,7 @@ int Application::findIndexOfDocument(const DocumentPtr& doc) const
 
 void Application::closeDocument(const DocumentPtr& doc)
 {
-    TDocStd_Application::Close(doc);
+    XCAFApp_Application::Close(doc);
     doc->signalNameChanged.disconnectAll();
     doc->signalFilePathChanged.disconnectAll();
     doc->signalEntityAdded.disconnectAll();
@@ -158,22 +139,19 @@ void Application::closeDocument(const DocumentPtr& doc)
     //doc->Main().ForgetAllAttributes(true/*clearChildren*/);
 }
 
-void Application::addTranslator(Application::Translator fn)
-{
-    if (fn)
-        d->m_vecTranslator.push_back(std::move(fn));
-}
-
-std::string_view Application::translate(const TextId& textId, int n) const
+void Application::defineMayoFormat(const ApplicationPtr& app)
 {
-    for (auto it = d->m_vecTranslator.rbegin(); it != d->m_vecTranslator.rend(); ++it) {
-        const Application::Translator& fn = *it;
-        std::string_view msg = fn(textId, n);
-        if (!msg.empty())
-            return msg;
-    }
-
-    return textId.key;
+    const char strFougueCopyright[] = "Copyright (c) 2024, Fougue Ltd. <https://www.fougue.pro>";
+    app->DefineFormat(
+        Document::NameFormatBinary, ApplicationI18N::textIdTr("Binary Mayo Document Format").data(), "myb",
+        new Document::FormatBinaryRetrievalDriver(app),
+        new BinXCAFDrivers_DocumentStorageDriver
+    );
+    app->DefineFormat(
+        Document::NameFormatXml, ApplicationI18N::textIdTr("XML Mayo Document Format").data(), "myx",
+        new Document::FormatXmlRetrievalDriver(app),
+        new XmlXCAFDrivers_DocumentStorageDriver(strFougueCopyright)
+    );
 }
 
 Span<const char*> Application::envOpenCascadeOptions()
@@ -215,7 +193,7 @@ void Application::NewDocument(const TCollection_ExtendedString&, OccHandle<TDocS
 #endif
 {
     // TODO: check format == "mayo" if not throw exception
-    // Extended from TDocStd_Application::NewDocument() implementation, ensure that in future
+    // Extended from XCAFApp_Application::NewDocument() implementation, ensure that in future
     // OpenCascade versions this code is still compatible!
     DocumentPtr newDoc = new Document(this);
     CDF_Application::Open(newDoc); // Add the document in the session
@@ -229,13 +207,7 @@ void Application::InitDocument(const OccHandle<CDM_Document>& doc) const
 void Application::InitDocument(const OccHandle<TDocStd_Document>& doc) const
 #endif
 {
-    TDocStd_Application::InitDocument(doc);
-    XCAFApp_Application::GetApplication()->InitDocument(doc);
-}
-
-Application::Application()
-    : d(new Private)
-{
+    XCAFApp_Application::InitDocument(doc);
 }
 
 void Application::notifyDocumentAboutToClose(Document::Identifier docIdent)
diff --git a/src/base/application.h b/src/base/application.h
index d733ce04..746433e5 100644
--- a/src/base/application.h
+++ b/src/base/application.h
@@ -11,22 +11,19 @@
 #include "occ_handle.h"
 #include "signal.h"
 #include "span.h"
-#include "text_id.h"
 
 #include <CDF_DirectoryIterator.hxx>
 #include <Standard_Version.hxx>
-#include <functional>
+#include <XCAFApp_Application.hxx>
 
 namespace Mayo {
 
 // Provides management of Document objects
-class Application : public TDocStd_Application {
+class Application : public XCAFApp_Application {
 public:
+    Application();
     ~Application();
 
-    // Global instance(singleton)
-    static const ApplicationPtr& instance();
-
     // Iterator over Documents contained in an Application
     struct DocumentIterator : private CDF_DirectoryIterator {
         DocumentIterator(const ApplicationPtr& app);
@@ -49,13 +46,7 @@ class Application : public TDocStd_Application {
 
     void closeDocument(const DocumentPtr& doc);
 
-    // Provides internationalization support for text output
-    //     1st arg: message to be translated(TextId = context+key)
-    //     2nd arg: when != -1 used to choose an appropriate form for the translation(e.g. "%n file found" vs. "%n files found")
-    //     returns: translated message
-    using Translator = std::function<std::string_view (const TextId&, int)>;
-    void addTranslator(Translator fn);
-    std::string_view translate(const TextId& textId, int n = -1) const;
+    static void defineMayoFormat(const ApplicationPtr& app);
 
     static Span<const char*> envOpenCascadeOptions();
     static Span<const char*> envOpenCascadePaths();
@@ -83,12 +74,11 @@ class Application : public TDocStd_Application {
 // -> Can't do because PCDM_RetrievalDriver subclasses create explicitly "new TDocStd_Document(...)"
 //    This would break TDocStd_Application::Open(...)
 
-    DEFINE_STANDARD_RTTI_INLINE(Application, TDocStd_Application)
+    DEFINE_STANDARD_RTTI_INLINE(Application, XCAFApp_Application)
 
 private: // Implementation
     friend class Document;
 
-    Application();
     void notifyDocumentAboutToClose(Document::Identifier docIdent);
     void addDocument(const DocumentPtr& doc);
 
diff --git a/src/base/application_ptr.h b/src/base/application_ptr.h
index a8cbbc2a..bab06e0f 100644
--- a/src/base/application_ptr.h
+++ b/src/base/application_ptr.h
@@ -7,12 +7,12 @@
 #pragma once
 
 #include "occ_handle.h"
-#include <TDocStd_Application.hxx>
+#include <XCAFApp_Application.hxx>
 
 namespace Mayo {
 
 class Application;
-DEFINE_STANDARD_HANDLE(Application, TDocStd_Application)
+DEFINE_STANDARD_HANDLE(Application, XCAFApp_Application)
 using ApplicationPtr = OccHandle<Application>;
 
 } // namespace Mayo
diff --git a/src/base/text_id.cpp b/src/base/text_id.cpp
index c821ea4f..a8847bf9 100644
--- a/src/base/text_id.cpp
+++ b/src/base/text_id.cpp
@@ -5,13 +5,24 @@
 ****************************************************************************/
 
 #include "text_id.h"
-#include "application.h"
+
+#include <vector>
 
 namespace Mayo {
 
+namespace {
+
+std::vector<TextId::TranslatorFunctionPtr>& getTranslatorFunctions()
+{
+    static std::vector<TextId::TranslatorFunctionPtr> vec;
+    return vec;
+}
+
+} // namespace
+
 std::string_view TextId::tr(int n) const
 {
-    return Application::instance()->translate(*this, n);
+    return TextId::translate(*this, n);
 }
 
 bool TextId::isEmpty() const
@@ -19,4 +30,23 @@ bool TextId::isEmpty() const
     return this->key.empty();
 }
 
+void TextId::addTranslatorFunction(TranslatorFunctionPtr fn)
+{
+    if (fn)
+        getTranslatorFunctions().push_back(fn);
+}
+
+std::string_view TextId::translate(const TextId& textId, int n)
+{
+    for (auto it = getTranslatorFunctions().rbegin(); it != getTranslatorFunctions().rend(); ++it) {
+        TranslatorFunctionPtr fn = *it;
+        std::string_view msg = fn(textId, n);
+        if (!msg.empty())
+            return msg;
+    }
+
+    return textId.key;
+}
+
+
 } // namespace Mayo
diff --git a/src/base/text_id.h b/src/base/text_id.h
index 7e19effd..9e5d2dbb 100644
--- a/src/base/text_id.h
+++ b/src/base/text_id.h
@@ -37,6 +37,15 @@ struct TextId {
 
     // Whether source text(key) is empty or not
     bool isEmpty() const;
+
+    // Provides internationalization support for text output
+    //     1st arg: message to be translated(TextId = context+key)
+    //     2nd arg: when != -1 used to choose an appropriate form for the translation(e.g. "%n file found" vs. "%n files found")
+    //     returns: translated message
+    using TranslatorFunction = std::string_view(const TextId&, int);
+    using TranslatorFunctionPtr = TranslatorFunction*;
+    static void addTranslatorFunction(TranslatorFunctionPtr fn);
+    static std::string_view translate(const TextId& textId, int n = -1);
 };
 
 } // namespace Mayo
diff --git a/src/cli/cli_export.cpp b/src/cli/cli_export.cpp
index 989267cc..2437a1a3 100644
--- a/src/cli/cli_export.cpp
+++ b/src/cli/cli_export.cpp
@@ -166,7 +166,10 @@ void exportDocument(const DocumentPtr& doc, const FilePath& filepath, Helper* he
 } // namespace
 
 void cli_asyncExportDocuments(
-        Application* app, const CliExportArgs& args, std::function<void(int)> fnContinuation)
+        const ApplicationPtr& app,
+        const CliExportArgs& args,
+        std::function<void(int)> fnContinuation
+    )
 {
     auto helper = new Helper; // Allocated on heap because current function is asynchronous
     auto taskMgr = &helper->taskMgr;
diff --git a/src/cli/cli_export.h b/src/cli/cli_export.h
index e57944b6..04e3ce9b 100644
--- a/src/cli/cli_export.h
+++ b/src/cli/cli_export.h
@@ -6,6 +6,7 @@
 
 #pragma once
 
+#include "../base/application_ptr.h"
 #include "../base/filepath.h"
 #include "../base/span.h"
 
@@ -13,8 +14,6 @@
 
 namespace Mayo {
 
-class Application;
-
 // Contains arguments for the cli_asyncExportDocuments() function
 struct CliExportArgs {
     bool progressReport = true;
@@ -25,7 +24,7 @@ struct CliExportArgs {
 // Asynchronously exports input file(s) listed in 'args'
 // Calls 'fnContinuation' at the end of execution
 void cli_asyncExportDocuments(
-        Application* app,
+        const ApplicationPtr& app,
         const CliExportArgs& args,
         std::function<void(int)> fnContinuation
 );
diff --git a/src/cli/main.cpp b/src/cli/main.cpp
index 46a694c9..e3512d2f 100644
--- a/src/cli/main.cpp
+++ b/src/cli/main.cpp
@@ -405,8 +405,8 @@ static int runApp(QCoreApplication* qtApp)
     }
 
     // Initialize Base application
-    auto app = Application::instance().get();
-    app->addTranslator(&qtAppTranslate); // Set Qt i18n backend
+    auto app = appModule->application();
+    TextId::addTranslatorFunction(&qtAppTranslate); // Set Qt i18n backend
 #ifdef MAYO_OS_WINDOWS
     initOpenCascadeEnvironment("opencascade.conf");
 #endif
diff --git a/tests/test_app.cpp b/tests/test_app.cpp
index 71933659..0db98011 100644
--- a/tests/test_app.cpp
+++ b/tests/test_app.cpp
@@ -66,7 +66,7 @@ RecentFile createRecentFile(const QPixmap& thumbnail)
 
 void TestApp::DocumentFilesWatcher_test()
 {
-    auto app = Application::instance();
+    auto app = makeOccHandle<Application>();
 
     DocumentFilesWatcher docFilesWatcher(app);
     docFilesWatcher.enable(true);
@@ -87,10 +87,6 @@ void TestApp::DocumentFilesWatcher_test()
     fnCopyCadFile();
     DocumentPtr doc = app->newDocument();
     doc->setFilePath(cadFilePath);
-    auto _ = gsl::finally([=]{
-        if (app->findIndexOfDocument(doc) != -1)
-            app->closeDocument(doc);
-    });
 
     // Check file change on document is caught
     fnCopyCadFile();
diff --git a/tests/test_base.cpp b/tests/test_base.cpp
index eb6fb229..d4ab9c61 100644
--- a/tests/test_base.cpp
+++ b/tests/test_base.cpp
@@ -188,7 +188,7 @@ struct SignalEmitSpy {
 
 void TestBase::Application_test()
 {
-    auto app = Application::instance();
+    auto app = makeOccHandle<Application>();
     auto fnImportInDocument = [=](const DocumentPtr& doc, const FilePath& fp) {
         return m_ioSystem->importInDocument()
                 .targetDocument(doc)
@@ -259,9 +259,10 @@ void TestBase::Application_test()
 
 void TestBase::DocumentRefCount_test()
 {
-    DocumentPtr doc = Application::instance()->newDocument();
+    auto app = makeOccHandle<Application>();
+    DocumentPtr doc = app->newDocument();
     QVERIFY(doc->GetRefCount() > 1);
-    Application::instance()->closeDocument(doc);
+    app->closeDocument(doc);
     QCOMPARE(doc->GetRefCount(), 1);
 }
 
@@ -609,7 +610,7 @@ void TestBase::IO_bugGitHub166_test()
     QFETCH(QString, strOutputFilePath);
     QFETCH(IO::Format, outputFormat);
 
-    auto app = Application::instance();
+    auto app = makeOccHandle<Application>();
     DocumentPtr doc = app->newDocument();
     const bool okImport = m_ioSystem->importInDocument()
             .targetDocument(doc)
@@ -665,7 +666,7 @@ void TestBase::IO_bugGitHub166_test_data()
 
 void TestBase::IO_bugGitHub258_test()
 {
-    auto app = Application::instance();
+    auto app = makeOccHandle<Application>();
     DocumentPtr doc = app->newDocument();
     const bool okImport = m_ioSystem->importInDocument()
                               .targetDocument(doc)
@@ -681,8 +682,6 @@ void TestBase::IO_bugGitHub258_test()
     QVERIFY(!triangulation.IsNull());
     QCOMPARE(triangulation->NbNodes(), 24);
     QCOMPARE(triangulation->NbTriangles(), 12);
-
-    app->closeDocument(doc);
 }
 
 void TestBase::DoubleToString_test()
diff --git a/tests/test_measure.cpp b/tests/test_measure.cpp
index 061f93e3..d8f6ea63 100644
--- a/tests/test_measure.cpp
+++ b/tests/test_measure.cpp
@@ -182,7 +182,8 @@ void TestMeasure::BRepArea_TriangulationFace_test()
     const bool okRead = reader.readFile("tests/inputs/face_trsf_scale_almost_1.stl", progress);
     QVERIFY(okRead);
 
-    auto doc = Application::instance()->newDocument();
+    auto app = makeOccHandle<Application>();
+    auto doc = app->newDocument();
     const TDF_LabelSequence seqLabel = reader.transfer(doc, progress);
     QCOMPARE(seqLabel.Size(), 1);
     const TopoDS_Shape shape = doc->xcaf().shape(seqLabel.First());
@@ -193,7 +194,7 @@ void TestMeasure::BRepArea_TriangulationFace_test()
 void TestMeasure::BRepBoundingBox_Sphere_test()
 {
     const double sphereRadius = 50.;
-    const TopoDS_Shape sphereShape = BRepPrimAPI_MakeSphere(50.);
+    const TopoDS_Shape sphereShape = BRepPrimAPI_MakeSphere(sphereRadius);
     const MeasureBoundingBox bndBox = MeasureToolBRep::brepBoundingBox(sphereShape);
     QVERIFY(bndBox.cornerMin.IsEqual(gp_Pnt{-sphereRadius, -sphereRadius, -sphereRadius}, Precision::Confusion()));
     QVERIFY(bndBox.cornerMax.IsEqual(gp_Pnt{sphereRadius, sphereRadius, sphereRadius}, Precision::Confusion()));