diff --git a/app/src/main/AndroidManifest.xml b/app/src/main/AndroidManifest.xml
index 928ad79..c445434 100644
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@@ -1,5 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
     package="uk.org.openseizuredetector"
     android:versionCode="70"
     android:versionName="3.2.0">
@@ -26,7 +27,8 @@
         android:icon="@drawable/star_of_life_48x48"
         android:label="@string/app_name"
         android:networkSecurityConfig="@xml/network_security_config"
-        android:theme="@style/Theme.AppCompat">
+        android:theme="@style/Theme.AppCompat"
+        >
         <activity android:name=".DBQueryActivity"></activity>
         <!-- android:usesCleartextTraffic="true" -->
         <activity android:name=".StartupActivity">
diff --git a/app/src/main/java/uk/org/openseizuredetector/AuthDialog.java b/app/src/main/java/uk/org/openseizuredetector/AuthDialog.java
new file mode 100644
index 0000000..ed4d645
--- /dev/null
+++ b/app/src/main/java/uk/org/openseizuredetector/AuthDialog.java
@@ -0,0 +1,78 @@
+package uk.org.openseizuredetector;
+
+
+import android.app.Activity;
+import android.content.Context;
+import android.os.Bundle;
+import android.support.v4.app.DialogFragment;
+import android.util.Log;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.Button;
+import android.widget.EditText;
+
+public class AuthDialog extends DialogFragment {
+    private String TAG = "AuthDialog";
+    private AuthDialogInterface mListener;
+    private Context mContext;
+    private EditText mUnameEt;
+    private EditText mPasswdEt;
+
+    @Override
+    public View onCreateView(
+            LayoutInflater inflater,
+            ViewGroup container,
+            Bundle savedInstanceState) {
+        Log.v(TAG, "onCreateView()");
+        View v = inflater.inflate(R.layout.dialog_authenticate,
+                container, false);
+        Button cancelBtn =
+                (Button) v.findViewById(R.id.cancelBtn);
+        cancelBtn.setOnClickListener(onCancel);
+        Button OKBtn = (Button) v.findViewById(R.id.OKBtn);
+        OKBtn.setOnClickListener(onOK);
+
+        mUnameEt = (EditText) v.findViewById(R.id.username);
+        mPasswdEt = (EditText) v.findViewById(R.id.password);
+
+        return v;
+
+    }
+
+    View.OnClickListener onCancel =
+            new View.OnClickListener() {
+                @Override
+                public void onClick(View view) {
+                    Log.v(TAG, "onCancel");
+                    //m_status=false;
+                    mListener.onDialogDone(false);
+                    dismiss();
+                }
+            };
+
+    View.OnClickListener onOK =
+            new View.OnClickListener() {
+                @Override
+                public void onClick(View view) {
+                    //m_status=true;
+                    Log.v(TAG, "onOK()");
+                    String uname = mUnameEt.getText().toString();
+                    String passwd = mPasswdEt.getText().toString();
+                    Log.v(TAG,"onOK() - uname="+uname+", passwd="+passwd);
+                    mListener.onDialogDone(true);
+                    dismiss();
+                }
+            };
+
+    @Override
+    public void onAttach(Context context) {
+        super.onAttach(context);
+        try {
+            mListener = (AuthDialogInterface) context;
+        } catch (ClassCastException e) {
+            throw new ClassCastException(context.toString()
+                    + " must implement dialogDoneistener");
+        }
+    }
+}
diff --git a/app/src/main/java/uk/org/openseizuredetector/AuthDialogInterface.java b/app/src/main/java/uk/org/openseizuredetector/AuthDialogInterface.java
new file mode 100644
index 0000000..f59b062
--- /dev/null
+++ b/app/src/main/java/uk/org/openseizuredetector/AuthDialogInterface.java
@@ -0,0 +1,5 @@
+package uk.org.openseizuredetector;
+
+public interface AuthDialogInterface {
+    void onDialogDone(boolean state);
+}
\ No newline at end of file
diff --git a/app/src/main/java/uk/org/openseizuredetector/LogManager.java b/app/src/main/java/uk/org/openseizuredetector/LogManager.java
index 761d694..4f48765 100644
--- a/app/src/main/java/uk/org/openseizuredetector/LogManager.java
+++ b/app/src/main/java/uk/org/openseizuredetector/LogManager.java
@@ -175,6 +175,21 @@ public class LogManager {
         uploadSdData();
     }
 
+
+    /**
+     * Authenticate using the WebAPI to obtain a token for future API requests.
+     * @param uname - user name
+     * @param passwd - password
+     */
+    public void authenticate(String uname, String passwd) {
+        Log.v(TAG, "authenticate()");
+        // FIXME - this does not work!!!!
+        String dataStr = "data string to upload";
+        //new PostDataTask().execute("http://" + mOSDUrl + ":8080/data", dataStr, mOSDUname, mOSDPasswd);
+        new PostDataTask().execute("http://192.168.43.175:8765/datapoints/add", dataStr, mOSDUname, mOSDPasswd);
+
+    }
+
     /**
      * Upload a batch of seizure detector data records to the server..
      * Uses the UploadSdDataTask class to upload the data in the
diff --git a/app/src/main/java/uk/org/openseizuredetector/LogManagerActivity.java b/app/src/main/java/uk/org/openseizuredetector/LogManagerActivity.java
index 5da2319..27c0d0c 100644
--- a/app/src/main/java/uk/org/openseizuredetector/LogManagerActivity.java
+++ b/app/src/main/java/uk/org/openseizuredetector/LogManagerActivity.java
@@ -1,22 +1,25 @@
 package uk.org.openseizuredetector;
 
-import android.app.Activity;
-import android.support.v7.app.AppCompatActivity;
 import android.os.Bundle;
+import android.support.v4.app.FragmentActivity;
+import android.util.Log;
+import android.view.View;
+import android.widget.Button;
 import android.widget.ListView;
 
-import java.util.Date;
-
 import uk.org.openseizuredetector.EventLogManager.EventLogListAdapter;
 import uk.org.openseizuredetector.EventLogManager.EventLogManager;
 import uk.org.openseizuredetector.EventLogManager.LogEntryModel;
 
-public class LogManagerActivity extends Activity {
 
+public class LogManagerActivity extends FragmentActivity
+implements AuthDialogInterface {
+    private String TAG = "LogManagerActivity";
     private EventLogListAdapter mEventLogListAdapter;
     private ListView mEventLogListView;
     private EventLogManager mElm;
 
+
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
@@ -28,15 +31,32 @@ public class LogManagerActivity extends Activity {
         lem.setDataJSON("[]");
         lem.setAlarmState(1);
 
-        mElm = new EventLogManager(this);
-        mElm.addRow(lem);
+        //mElm = new EventLogManager(this);
+        //mElm.addRow(lem);
 
-        mEventLogListAdapter = new EventLogListAdapter(this);
-        mEventLogListView = (ListView) findViewById(R.id.eventLogListView);
-        mEventLogListView.setAdapter(mEventLogListAdapter);
+        //mEventLogListAdapter = new EventLogListAdapter(this);
+        //mEventLogListView = (ListView) findViewById(R.id.eventLogListView);
+        //mEventLogListView.setAdapter(mEventLogListAdapter);
 
+        Button b;
 
+        b = (Button) findViewById(R.id.authenticate_button);
+        b.setOnClickListener(new View.OnClickListener() {
+            @Override
+            public void onClick(View view) {
+                Log.v(TAG, "authenticate button clicked");
+                AuthDialog authDialog = new AuthDialog();
+                authDialog.show(getSupportFragmentManager(),"authDialog");
+            }
+        });
     }
 
+    public void updateUi() {
+        Log.v(TAG, "updateUi");
+    }
 
-}
+    public void onDialogDone(boolean State) {
+        Log.v(TAG,"onDialogDOne()");
+    }
+
+}
\ No newline at end of file
diff --git a/app/src/main/java/uk/org/openseizuredetector/MainActivity.java b/app/src/main/java/uk/org/openseizuredetector/MainActivity.java
index d9f9270..52bb7d9 100644
--- a/app/src/main/java/uk/org/openseizuredetector/MainActivity.java
+++ b/app/src/main/java/uk/org/openseizuredetector/MainActivity.java
@@ -266,6 +266,17 @@ public class MainActivity extends AppCompatActivity {
                     Log.i(TAG, "exception starting log manager activity " + ex.toString());
                 }
                 return true;
+            case R.id.action_logmanager:
+                Log.i(TAG, "action_logmanager");
+                try {
+                    Intent intent = new Intent(
+                            MainActivity.this,
+                            LogManagerActivity.class);
+                    this.startActivity(intent);
+                } catch (Exception ex) {
+                    Log.i(TAG, "exception starting log manager activity " + ex.toString());
+                }
+                return true;
             case R.id.action_settings:
                 Log.i(TAG, "action_settings");
                 try {
diff --git a/app/src/main/java/uk/org/openseizuredetector/data/LoginDataSource.java b/app/src/main/java/uk/org/openseizuredetector/data/LoginDataSource.java
new file mode 100644
index 0000000..224ceed
--- /dev/null
+++ b/app/src/main/java/uk/org/openseizuredetector/data/LoginDataSource.java
@@ -0,0 +1,29 @@
+package uk.org.openseizuredetector.data;
+
+import uk.org.openseizuredetector.data.model.LoggedInUser;
+
+import java.io.IOException;
+
+/**
+ * Class that handles authentication w/ login credentials and retrieves user information.
+ */
+public class LoginDataSource {
+
+    public Result<LoggedInUser> login(String username, String password) {
+
+        try {
+            // TODO: handle loggedInUser authentication
+            LoggedInUser fakeUser =
+                    new LoggedInUser(
+                            java.util.UUID.randomUUID().toString(),
+                            "Jane Doe");
+            return new Result.Success<>(fakeUser);
+        } catch (Exception e) {
+            return new Result.Error(new IOException("Error logging in", e));
+        }
+    }
+
+    public void logout() {
+        // TODO: revoke authentication
+    }
+}
diff --git a/app/src/main/java/uk/org/openseizuredetector/data/LoginRepository.java b/app/src/main/java/uk/org/openseizuredetector/data/LoginRepository.java
new file mode 100644
index 0000000..75df6a2
--- /dev/null
+++ b/app/src/main/java/uk/org/openseizuredetector/data/LoginRepository.java
@@ -0,0 +1,54 @@
+package uk.org.openseizuredetector.data;
+
+import uk.org.openseizuredetector.data.model.LoggedInUser;
+
+/**
+ * Class that requests authentication and user information from the remote data source and
+ * maintains an in-memory cache of login status and user credentials information.
+ */
+public class LoginRepository {
+
+    private static volatile LoginRepository instance;
+
+    private LoginDataSource dataSource;
+
+    // If user credentials will be cached in local storage, it is recommended it be encrypted
+    // @see https://developer.android.com/training/articles/keystore
+    private LoggedInUser user = null;
+
+    // private constructor : singleton access
+    private LoginRepository(LoginDataSource dataSource) {
+        this.dataSource = dataSource;
+    }
+
+    public static LoginRepository getInstance(LoginDataSource dataSource) {
+        if (instance == null) {
+            instance = new LoginRepository(dataSource);
+        }
+        return instance;
+    }
+
+    public boolean isLoggedIn() {
+        return user != null;
+    }
+
+    public void logout() {
+        user = null;
+        dataSource.logout();
+    }
+
+    private void setLoggedInUser(LoggedInUser user) {
+        this.user = user;
+        // If user credentials will be cached in local storage, it is recommended it be encrypted
+        // @see https://developer.android.com/training/articles/keystore
+    }
+
+    public Result<LoggedInUser> login(String username, String password) {
+        // handle login
+        Result<LoggedInUser> result = dataSource.login(username, password);
+        if (result instanceof Result.Success) {
+            setLoggedInUser(((Result.Success<LoggedInUser>) result).getData());
+        }
+        return result;
+    }
+}
diff --git a/app/src/main/java/uk/org/openseizuredetector/data/Result.java b/app/src/main/java/uk/org/openseizuredetector/data/Result.java
new file mode 100644
index 0000000..cc92d09
--- /dev/null
+++ b/app/src/main/java/uk/org/openseizuredetector/data/Result.java
@@ -0,0 +1,48 @@
+package uk.org.openseizuredetector.data;
+
+/**
+ * A generic class that holds a result success w/ data or an error exception.
+ */
+public class Result<T> {
+    // hide the private constructor to limit subclass types (Success, Error)
+    private Result() {
+    }
+
+    @Override
+    public String toString() {
+        if (this instanceof Result.Success) {
+            Result.Success success = (Result.Success) this;
+            return "Success[data=" + success.getData().toString() + "]";
+        } else if (this instanceof Result.Error) {
+            Result.Error error = (Result.Error) this;
+            return "Error[exception=" + error.getError().toString() + "]";
+        }
+        return "";
+    }
+
+    // Success sub-class
+    public final static class Success<T> extends Result {
+        private T data;
+
+        public Success(T data) {
+            this.data = data;
+        }
+
+        public T getData() {
+            return this.data;
+        }
+    }
+
+    // Error sub-class
+    public final static class Error extends Result {
+        private Exception error;
+
+        public Error(Exception error) {
+            this.error = error;
+        }
+
+        public Exception getError() {
+            return this.error;
+        }
+    }
+}
diff --git a/app/src/main/java/uk/org/openseizuredetector/data/model/LoggedInUser.java b/app/src/main/java/uk/org/openseizuredetector/data/model/LoggedInUser.java
new file mode 100644
index 0000000..806c32d
--- /dev/null
+++ b/app/src/main/java/uk/org/openseizuredetector/data/model/LoggedInUser.java
@@ -0,0 +1,23 @@
+package uk.org.openseizuredetector.data.model;
+
+/**
+ * Data class that captures user information for logged in users retrieved from LoginRepository
+ */
+public class LoggedInUser {
+
+    private String userId;
+    private String displayName;
+
+    public LoggedInUser(String userId, String displayName) {
+        this.userId = userId;
+        this.displayName = displayName;
+    }
+
+    public String getUserId() {
+        return userId;
+    }
+
+    public String getDisplayName() {
+        return displayName;
+    }
+}
diff --git a/app/src/main/res/layout/activity_log_manager.xml b/app/src/main/res/layout/activity_log_manager.xml
index 5143735..807bf4f 100644
--- a/app/src/main/res/layout/activity_log_manager.xml
+++ b/app/src/main/res/layout/activity_log_manager.xml
@@ -9,18 +9,37 @@
     android:paddingTop="@dimen/activity_vertical_margin"
     tools:context="uk.org.openseizuredetector.LogManager">
 
+
+
     <TextView
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:textAppearance="?android:attr/textAppearanceLarge"
-        android:text="Large Text"
-        android:id="@+id/textView2"
+        android:text="@string/not_authenticated"
+        android:id="@+id/authStatusTv"
         />
+    <Button
+        android:id="@+id/authenticate_button"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_weight="1"
+        android:text="@string/authenticate" />
 
+<!--
     <ListView
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:id="@+id/eventLogListView"
         android:layout_marginTop="97dp" />
 
+    <EditText
+        android:id="@+id/editText"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_weight="1"
+        android:ems="10"
+        android:inputType="textPersonName"
+        android:text="Name" />
+-->
+
 </LinearLayout>
diff --git a/app/src/main/res/layout/dialog_authenticate.xml b/app/src/main/res/layout/dialog_authenticate.xml
new file mode 100644
index 0000000..be61d07
--- /dev/null
+++ b/app/src/main/res/layout/dialog_authenticate.xml
@@ -0,0 +1,52 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:orientation="vertical"
+    android:layout_width="wrap_content"
+    android:layout_height="wrap_content">
+    <ImageView
+        android:src="@drawable/star_of_life_24x24"
+        android:layout_width="match_parent"
+        android:layout_height="64dp"
+        android:scaleType="center"
+        android:background="#FFFFBB33"
+        android:contentDescription="@string/app_name" />
+    <EditText
+        android:id="@+id/username"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="16dp"
+        android:layout_marginLeft="4dp"
+        android:layout_marginRight="4dp"
+        android:layout_marginBottom="4dp"
+        android:hint="username" />
+    <EditText
+        android:id="@+id/password"
+        android:inputType="textPassword"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="4dp"
+        android:layout_marginLeft="4dp"
+        android:layout_marginRight="4dp"
+        android:layout_marginBottom="16dp"
+        android:fontFamily="sans-serif"
+        android:hint="password"/>
+    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+        android:orientation="horizontal"
+        android:layout_width="fill_parent"
+        android:layout_height="wrap_content">
+        <Button
+            android:id="@+id/cancelBtn"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_weight="1"
+            android:text="@string/cancel" />
+        <Button
+            android:id="@+id/OKBtn"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_weight="1"
+            android:text="@string/authenticate" />
+    </LinearLayout>
+
+</LinearLayout>
+
diff --git a/app/src/main/res/menu/main_activity_actions.xml b/app/src/main/res/menu/main_activity_actions.xml
index 5bba06b..d99d335 100644
--- a/app/src/main/res/menu/main_activity_actions.xml
+++ b/app/src/main/res/menu/main_activity_actions.xml
@@ -46,6 +46,13 @@
         android:showAsAction="never|withText"
         android:title="Test SMS Alarm Notification" />
 
+    <item
+        android:id="@+id/action_logmanager"
+        android:icon="@drawable/ic_action_settings"
+        android:showAsAction="never|withText"
+        android:title="Data Log Manager"
+        android:enabled="true"
+        />
 
     <item
         android:id="@+id/action_logs"
diff --git a/app/src/main/res/values/dimens.xml b/app/src/main/res/values/dimens.xml
index 47c8224..f33fd20 100644
--- a/app/src/main/res/values/dimens.xml
+++ b/app/src/main/res/values/dimens.xml
@@ -2,4 +2,7 @@
     <!-- Default screen margins, per the Android Design guidelines. -->
     <dimen name="activity_horizontal_margin">16dp</dimen>
     <dimen name="activity_vertical_margin">16dp</dimen>
+    <!-- Default screen margins, per the Android Design guidelines. -->
+    <dimen name="fragment_horizontal_margin">16dp</dimen>
+    <dimen name="fragment_vertical_margin">16dp</dimen>
 </resources>
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index 8152b84..aec55a8 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -79,4 +79,16 @@
     <string name="CancelAudibleAlarms">Cancel Audible Alarms (temporarily)</string>
     <string name="AudibleAlarmsOff">Audible Alarms OFF</string>
     <string name="Fault">FAULT</string>
+    <string name="authenticate">Authenticate</string>
+    <string name="not_authenticated">Not Authenticated</string>
+    <string name="cancel">Cancel</string>
+    <!-- Strings related to login -->
+    <string name="prompt_email">Email</string>
+    <string name="prompt_password">Password</string>
+    <string name="action_sign_in">Sign in or register</string>
+    <string name="action_sign_in_short">Sign in</string>
+    <string name="welcome">"Welcome!"</string>
+    <string name="invalid_username">Not a valid username</string>
+    <string name="invalid_password">Password must be >5 characters</string>
+    <string name="login_failed">"Login failed"</string>
 </resources>
diff --git a/app/src/main/res/xml/logmanager_prefs.xml b/app/src/main/res/xml/logmanager_prefs.xml
new file mode 100644
index 0000000..f1d0f8f
--- /dev/null
+++ b/app/src/main/res/xml/logmanager_prefs.xml
@@ -0,0 +1,59 @@
+<?xml version="1.0" encoding="utf-8"?>
+<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android">
+    <EditTextPreference
+        android:defaultValue="https://osd.dynu.net/"
+        android:key="serverUrl"
+        android:title="Server URL"
+        android:summary="URL of OpenSeizureDetector Data Log Server"
+        />
+    <CheckBoxPreference
+        android:defaultValue="true"
+        android:key="LogToServer"
+        android:summary="Log Data to OpenSeizureDetector Server"
+        android:title="Log to Server" />
+    <CheckBoxPreference
+        android:defaultValue="false"
+        android:key="UploadOverMobileNetwork"
+        android:summary="Upload Data when using Mobile Network"
+        android:title="Use Mobile Network" />
+    <EditTextPreference
+        android:defaultValue="password"
+        android:key="OSDPasswd"
+        android:summary="Password for remote data logging."
+        android:title="Remote Password" />
+
+    <CheckBoxPreference
+        android:defaultValue="false"
+        android:key="PreventSleep"
+        android:summary="Prevent the screen from blanking while the application is running."
+        android:title="Prevent the screen from blanking." />
+    <EditTextPreference
+        android:defaultValue="1000"
+        android:key="UpdatePeriod"
+        android:summary="Display update period in miliseconds."
+        android:title="Display Update Period (ms)." />
+    <CheckBoxPreference
+        android:defaultValue="false"
+        android:key="AutoStart"
+        android:summary="Auto Start App on Boot"
+        android:title="Auto Start App on Boot"
+        android:enabled="true"
+        />
+
+    <EditTextPreference
+        android:defaultValue=""
+        android:key="AppVersionName"
+        android:summary="App Version Number - used to decide whether to display the welcome message or not."
+        android:title="App Version Number" />
+<!--
+    <CheckBoxPreference
+        android:defaultValue="false"
+        android:key="UseIpCamera"
+        android:summary="Use IP Camera to View Images"
+        android:title="Enable IP Camera"
+        android:enabled="false"
+        />
+        -->
+
+
+</PreferenceScreen>