diff --git a/nx/include/switch/services/applet.h b/nx/include/switch/services/applet.h
index 865710b7..c9db8a11 100644
--- a/nx/include/switch/services/applet.h
+++ b/nx/include/switch/services/applet.h
@@ -14,6 +14,7 @@
 #include "../services/pm.h"
 #include "../kernel/tmem.h"
 #include "../kernel/event.h"
+#include "../nacp.h"
 
 /// AppletType
 typedef enum {
@@ -1084,6 +1085,11 @@ Result appletRequestLaunchApplication(u64 titleID, AppletStorage* s);
  */
 Result appletRequestLaunchApplicationForQuest(u64 titleID, AppletStorage* s, const AppletApplicationAttributeForQuest *attr);
 
+/**
+ * @brief Gets the DesiredLanguage for the current host title control.nacp.
+ * @note Only available with AppletType_*Application.
+ * @param[out] LanguageCode Output LanguageCode, see set.h.
+ */
 Result appletGetDesiredLanguage(u64 *LanguageCode);
 
 /// Only available with AppletType_*Application.
@@ -1352,6 +1358,13 @@ Result appletGetLibraryAppletInfo(LibAppletInfo *info);
  */
 Result appletGetMainAppletIdentityInfo(AppletIdentityInfo *info);
 
+/**
+ * @brief CanUseApplicationCore
+ * @note Only available with AppletType_LibraryApplet.
+ * @param[out] out Output flag.
+ */
+Result appletCanUseApplicationCore(bool *out);
+
 /**
  * @brief Gets the \ref AppletIdentityInfo for the CallerApplet.
  * @note Only available with AppletType_LibraryApplet.
@@ -1359,6 +1372,13 @@ Result appletGetMainAppletIdentityInfo(AppletIdentityInfo *info);
  */
 Result appletGetCallerAppletIdentityInfo(AppletIdentityInfo *info);
 
+/**
+ * @brief Gets the \ref NacpStruct for the MainApplet.
+ * @note Only available with AppletType_LibraryApplet on [2.0.0+].
+ * @param[out] nacp \ref NacpStruct
+ */
+Result appletGetMainAppletApplicationControlProperty(NacpStruct *nacp);
+
 /**
  * @brief Gets an array of \ref AppletIdentityInfo for the CallerStack.
  * @note Only available with AppletType_LibraryApplet on [3.0.0+].
@@ -1375,6 +1395,13 @@ Result appletGetCallerAppletIdentityInfoStack(AppletIdentityInfo *stack, s32 cou
  */
 Result appletGetNextReturnDestinationAppletIdentityInfo(AppletIdentityInfo *info);
 
+/**
+ * @brief Gets the DesiredLanguage for the MainApplet.
+ * @note Only available with AppletType_LibraryApplet on [4.0.0+].
+ * @param[out] LanguageCode Output LanguageCode, see set.h.
+ */
+Result appletGetMainAppletApplicationDesiredLanguage(u64 *LanguageCode);
+
 // IFunctions for AppletType_OverlayApplet (IOverlayFunctions).
 
 /**
diff --git a/nx/source/services/applet.c b/nx/source/services/applet.c
index c2b04f87..41930139 100644
--- a/nx/source/services/applet.c
+++ b/nx/source/services/applet.c
@@ -14,6 +14,7 @@
 #include "services/sm.h"
 #include "runtime/env.h"
 #include "runtime/hosversion.h"
+#include "nacp.h"
 
 __attribute__((weak)) u32 __nx_applet_type = AppletType_Default;
 __attribute__((weak)) bool __nx_applet_auto_notifyrunning = true;
@@ -4086,6 +4087,13 @@ Result appletGetMainAppletIdentityInfo(AppletIdentityInfo *info) {
     return _appletGetIdentityInfo(&g_appletILibraryAppletSelfAccessor, info, 12);
 }
 
+Result appletCanUseApplicationCore(bool *out) {
+    if (__nx_applet_type != AppletType_LibraryApplet)
+        return MAKERESULT(Module_Libnx, LibnxError_NotInitialized);
+
+    return _appletCmdNoInOutBool(&g_appletILibraryAppletSelfAccessor, out, 13);
+}
+
 Result appletGetCallerAppletIdentityInfo(AppletIdentityInfo *info) {
     if (__nx_applet_type != AppletType_LibraryApplet)
         return MAKERESULT(Module_Libnx, LibnxError_NotInitialized);
@@ -4093,6 +4101,45 @@ Result appletGetCallerAppletIdentityInfo(AppletIdentityInfo *info) {
     return _appletGetIdentityInfo(&g_appletILibraryAppletSelfAccessor, info, 14);
 }
 
+Result appletGetMainAppletApplicationControlProperty(NacpStruct *nacp) {
+    if (__nx_applet_type != AppletType_LibraryApplet)
+        return MAKERESULT(Module_Libnx, LibnxError_NotInitialized);
+    if (hosversionBefore(2,0,0))
+        return MAKERESULT(Module_Libnx, LibnxError_IncompatSysVer);
+
+    IpcCommand c;
+    ipcInitialize(&c);
+
+    ipcAddRecvBuffer(&c, nacp, sizeof(*nacp), BufferType_Normal);
+
+    struct {
+        u64 magic;
+        u64 cmd_id;
+    } *raw;
+
+    raw = serviceIpcPrepareHeader(&g_appletILibraryAppletSelfAccessor, &c, sizeof(*raw));
+
+    raw->magic = SFCI_MAGIC;
+    raw->cmd_id = 15;
+
+    Result rc = serviceIpcDispatch(&g_appletILibraryAppletSelfAccessor);
+
+    if (R_SUCCEEDED(rc)) {
+        IpcParsedCommand r;
+        struct {
+            u64 magic;
+            u64 result;
+        } *resp;
+
+        serviceIpcParse(&g_appletILibraryAppletSelfAccessor, &r, sizeof(*resp));
+        resp = r.Raw;
+
+        rc = resp->result;
+    }
+
+    return rc;
+}
+
 Result appletGetCallerAppletIdentityInfoStack(AppletIdentityInfo *stack, s32 count, s32 *total_out) {
     if (__nx_applet_type != AppletType_LibraryApplet)
         return MAKERESULT(Module_Libnx, LibnxError_NotInitialized);
@@ -4145,6 +4192,15 @@ Result appletGetNextReturnDestinationAppletIdentityInfo(AppletIdentityInfo *info
     return _appletGetIdentityInfo(&g_appletILibraryAppletSelfAccessor, info, 18);
 }
 
+Result appletGetMainAppletApplicationDesiredLanguage(u64 *LanguageCode) {
+    if (__nx_applet_type != AppletType_LibraryApplet)
+        return MAKERESULT(Module_Libnx, LibnxError_NotInitialized);
+    if (hosversionBefore(4,0,0))
+        return MAKERESULT(Module_Libnx, LibnxError_IncompatSysVer);
+
+    return _appletCmdNoInOut64(&g_appletILibraryAppletSelfAccessor, LanguageCode, 60);
+}
+
 // IOverlayFunctions
 
 Result appletBeginToWatchShortHomeButtonMessage(void) {