add a couple info in the About section

app/src/main/AndroidManifest.xml

@@ -42,6 +42,7 @@
 
         <activity
             android:name="com.simplemobiletools.calculator.AboutActivity"
+            android:label="@string/about"
             android:screenOrientation="portrait"/>
     </application>
 </manifest>

app/src/main/java/com/simplemobiletools/calculator/AboutActivity.java

@@ -1,14 +1,52 @@
 package com.simplemobiletools.calculator;
 
+import android.content.res.Resources;
 import android.os.Bundle;
 import android.support.v7.app.AppCompatActivity;
+import android.text.Html;
+import android.text.method.LinkMovementMethod;
+import android.widget.TextView;
+
+import java.util.Calendar;
+
+import butterknife.Bind;
+import butterknife.ButterKnife;
 
 public class AboutActivity extends AppCompatActivity {
+    @Bind(R.id.about_copyright) TextView copyright;
+    @Bind(R.id.about_version) TextView version;
+    @Bind(R.id.about_email) TextView emailTV;
+    private Resources res;
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_about);
-        setTitle(getResources().getString(R.string.about));
+        ButterKnife.bind(this);
+        res = getResources();
+
+        setupEmail();
+        setupVersion();
+        setupCopyright();
+    }
+
+    private void setupEmail() {
+        final String email = res.getString(R.string.email);
+        final String appName = res.getString(R.string.app_name);
+        final String href = "<a href=\"mailto:" + email + "?subject=" + appName + "\">" + email + "</a>";
+        emailTV.setText(Html.fromHtml(href));
+        emailTV.setMovementMethod(LinkMovementMethod.getInstance());
+    }
+
+    private void setupVersion() {
+        final String versionName = BuildConfig.VERSION_NAME;
+        final String versionText = String.format(res.getString(R.string.version), versionName);
+        version.setText(versionText);
+    }
+
+    private void setupCopyright() {
+        final int year = Calendar.getInstance().get(Calendar.YEAR);
+        final String copyrightText = String.format(res.getString(R.string.copyright), year);
+        copyright.setText(copyrightText);
     }
 }

app/src/main/res/layout/activity_about.xml

@@ -3,4 +3,43 @@
     android:id="@+id/about_holder"
     xmlns:android="http://schemas.android.com/apk/res/android"
     android:layout_width="match_parent"
-    android:layout_height="match_parent"/>
+    android:layout_height="match_parent"
+    android:layout_margin="@dimen/activity_margin">
+
+    <TextView
+        android:id="@+id/about_website"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:autoLink="web"
+        android:text="@string/website"/>
+
+    <TextView
+        android:id="@+id/about_email_label"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_below="@+id/about_website"
+        android:layout_marginTop="@dimen/activity_margin"
+        android:text="@string/email_label"/>
+
+    <TextView
+        android:id="@+id/about_email"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_below="@+id/about_email_label"
+        android:text="@string/email"/>
+
+    <TextView
+        android:id="@+id/about_version"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_above="@+id/about_copyright"
+        android:gravity="center_horizontal"/>
+
+    <TextView
+        android:id="@+id/about_copyright"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_alignParentBottom="true"
+        android:gravity="center_horizontal"/>
+
+</RelativeLayout>

app/src/main/res/values/strings.xml

@@ -1,4 +1,9 @@
 <resources>
     <string name="app_name">Simple Calculator</string>
     <string name="about">About</string>
+    <string name="website">For more simple apps please visit:\nhttp://simplemobiletools.com</string>
+    <string name="email_label">You can send your feedback and new app suggestions at:</string>
+    <string name="email">hello@simplemobiletools.com</string>
+    <string name="version">v %1$s</string>
+    <string name="copyright">Copyright © Simple Mobile Tools %1$d</string>
 </resources>