added mainapplication class

app/src/main/AndroidManifest.xml

@@ -6,7 +6,8 @@
     <application android:label="@string/app_name"
                  android:icon="@drawable/ic_launcher"
                  android:theme="@style/AppTheme"
-                 android:largeHeap="true">
+                 android:largeHeap="true"
+                 android:name=".MainApplication">
         <activity android:name=".activity.MainActivity"
                   android:label="@string/app_name">
             <intent-filter>

app/src/main/java/com/nkanaev/comics/MainApplication.java

@@ -0,0 +1,24 @@
+package com.nkanaev.comics;
+
+import android.app.Application;
+import android.content.Context;
+import android.content.SharedPreferences;
+
+
+public class MainApplication extends Application {
+    private static Context mContext;
+
+    @Override
+    public void onCreate() {
+        super.onCreate();
+        mContext = this;
+    }
+
+    public static Context getAppContext() {
+        return mContext;
+    }
+
+    public static SharedPreferences getPreferences() {
+        return mContext.getSharedPreferences(Constants.SETTINGS_NAME, 0);
+    }
+}