[Galaxy S Advance I9070 Themes and Apps] P123456:
Mod the system ui for lock screen and recent apps in status bar. No extra running app required, just inbuild system keys. It will reduce the use of physical keys a bit.

Thanks hara74 for guide http://xdaforums.com/showpost.php?p=41120123&postcount=3

SystemUI.apk\res\layout\tw_status_bar_expanded_header.xml

Added lines in blue colour

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout android:gravity="center_vertical" android:orientation="horizontal" android:background="#ff000000" android:layout_width="fill_parent" android:layout_height="39.0dip" android:baselineAligned="false"
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:systemui="http://schemas.android.com/apk/res/com.android.systemui">
<com.android.systemui.statusbar.policy.Clock android:textAppearance="@style/TextAppearance.StatusBar.Expanded.Clock" android:textColor="#ffffffff" android:id="@id/clock" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginLeft="4.0dip" android:layout_marginTop="-3.0dip" android:singleLine="true" systemui:ampmSmall="true" />
<com.android.systemui.statusbar.policy.DateView android:textAppearance="@style/TextAppearance.StatusBar.Expanded.Date" android:textColor="[COLOR="DeepSkyBlue"]#ffffffff[/COLOR]" android:ellipsize="none" android:id="@id/date" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginLeft="2.0dip" android:layout_marginRight="2.0dip" android:maxLines="2" />
<com.android.systemui.statusbar.RotationToggle android:id="@id/rotation_lock_button" android:clickable="true" android:layout_width="32.0dip" android:layout_height="32.0dip" android:layout_margin="2.0dip" android:button="@drawable/ic_notify_rotation" android:contentDescription="@string/accessibility_rotation_lock_off" />
[COLOR="DeepSkyBlue"]<com.android.systemui.statusbar.policy.KeyButtonView android:id="@id/back" android:background="@drawable/tw_quick_panel_setting_button_bg" android:paddingLeft="2.0dip" android:paddingRight="2.0dip" android:focusable="true" android:layout_width="wrap_content" android:layout_height="fill_parent" android:src="@drawable/keylockwhite" android:layout_toLeftOf="@id/recent_apps" android:contentDescription="@string/accessibility_back" systemui:keyCode="26" />
<com.android.systemui.statusbar.policy.KeyButtonView android:id="@id/recent_apps" android:background="@drawable/tw_quick_panel_setting_button_bg" android:paddingLeft="2.0dip" android:paddingRight="2.0dip" android:focusable="true" android:layout_width="wrap_content" android:layout_height="fill_parent" android:src="@drawable/recentwhite" android:layout_toRightOf="@id/back" android:contentDescription="@string/accessibility_recent" systemui:keyCode="187" />[/COLOR]
<Space android:layout_width="0.0dip" android:layout_height="0.0dip" android:layout_weight="1.0" />
<ImageView android:layout_width="1.0dip" android:layout_height="25.0dip" android:layout_marginTop="7.0dip" android:layout_marginBottom="7.0dip" android:src="@drawable/tw_quick_panel_plnm_setting_dv" />
<RelativeLayout android:id="@id/settings_button" android:background="@drawable/tw_quick_panel_setting_button_bg" android:focusable="true" android:visibility="visible" android:layout_width="58.0dip" android:layout_height="39.0dip">
<ImageView android:id="@id/settings_button_icon" android:layout_width="wrap_content" android:layout_height="wrap_content" android:src="@drawable/43_notify_quicksettings_normal" android:scaleType="center" android:layout_centerHorizontal="true" android:layout_centerVertical="true" android:contentDescription="@string/accessibility_settings_button" />
</RelativeLayout>
</LinearLayout>

You can also add home button:

<com.android.systemui.statusbar.policy.KeyButtonView android:id="@id/home" android:background="@drawable/tw_quick_panel_setting_button_bg" android:paddingLeft="2.0dip" android:paddingRight="2.0dip" android:focusable="true" android:layout_width="wrap_content" android:layout_height="fill_parent" android:src="@drawable/ic_sysbar_home" android:layout_toRightOf="@id/back" android:contentDescription="@string/accessibility_recent" systemui:keyCode="3" />

long pressing home will show recent apps and long press of keylock will give Device options (Power off, Data network mode, Restart.. etc)

How to install:

1. Rename /system/app/SystemUI.apk to SystemUI.apk.bkp (for backup)

2. Copy the downloaded SystemUI.apk in the /system/app

3. Change permission: rw-r--r--

4. Reboot if required.

Icon layout and bug fixed in new BG trans 50% zip.