Android Tuner play.google.com.at
Following popular requests, this is the merging of Battery Monitor Widget, System Tuner and Multi Toggle Widget apps.
Best on rooted phones, works well on stock phones too.

Unique features not available elsewhere (requires root):

• Clean reboot
• Turn on/off APN, BT discovery, GPS & WiFi Localization
• Automatic backup of installed apps
•  Logcat reader for Android JellyBean 4.1.x
• Graphical monitoring widgets
• milli-amp consumption reporting

Full feature set (some require root access):

• File explorer (root, sd, network share, streaming)
• Application backups (auto, multiple version)
• Startup application manager*
• Application event control*
• System app uninstaller*
• System update cleaner*
• Monitoring (battery, cpu, network, memory)
• Logcat**, kernel message reader*
• App statistics since unplugged
• Task manager
• Auto-task killer
• Terminal emulator
• CPU tweaks (governor, frequency, voltages) relying on Kernel support*
• SD tweaks (cache size, scheduler)*
• Sysctl editor*
• Build.prop editor*
• Many notifications icons can be installed
• 1x1 and 2x1 text widgets
• 2x1, 3x1, 4x1, 4x2, 5x1 and 5x2 graphic widgets
• 1x1 and 4x1 toggle widgets***
• App optimizer (zipalign and database cleaner)
• Battery saver (cpu, switch off wifi, bt...)***

* Requires root access
** Requires root access on Android 4.1 and above
*** Requires root for full feature