ROM Manager

We’re kicking off this round-up with what might be the most important app there is for your Android-based device. As its name suggests, ROM Manager lets you save and restore your current ROM. But this app also allows you to restart in Recovery mode, install a ROM from the SD card, and partition the card. It's simply a must for anyone who enjoys playing around under the hood of Google's operating system.

What we like: Easy ROM switching, and the fact that you can restore a device’s original ROM.

Titanium Backup

When it comes to modifying certain system settings as root, you risk crashing your smartphone and losing all of your data, forcing you to reinstall Android. Fortunately, Titanium Backup lets you backup and restore all of the information on your device: apps, settings, SD card contents, and so on. This app might just prevent you from making a costly mistake.

What we like: Knowing that our data is safe, even from us!

JS Backup

JS Backup is a clear, simple, and intuitive data storage tool that allows you to save and restore contacts, call histories, text messages, calendars, bookmarks, system settings, shortcuts, alarms, dictionaries, apps, pictures, songs, playlists, and videos. In other words, it lets you save pretty much everything.

What we like: Uses the widely-accepted CSV format.

Android Terminal Emulator

A graphical interface is nice, but everyone knows that nothing beats a good old command-line interface (CLI) when you want to get into the guts of an operating system. Android Terminal Emulator lets you to do just that by providing access to Android’s CLI, where you can type in a host of commands, each one more exciting than the last.

What we like: Full access to Android’s underlying Linux command line interface.

ConnectBot

ConnectBot is an SSH client capable of managing several SSH sessions simultaneously, creating secure tunnels, and copy/pasting to and from other apps.

What we like: The possibility of accessing our home PCs while travelling.

Go Launcher EX

Go Launcher EX allows you to change the Android interface completely. It updates the widgets and icons, and makes folders behave just like those on the iPhone. The launcher, gestures, animations, and screen management receive an overhaul as well, and almost everything is customizable, letting you create a truly unique and personal user interface.

What we like: The ability to customize a device's UI beyond what Android typically facilitates.

System Tuner

System Tuner is one of those do-everything apps. Although it's a task manager at heart, this app also allows you to select what programs start with the phone, set the cache size for SD cards, tweak the CPU frequency, and monitor memory usage. It’s also possible to modify apps that are integrated into the ROM, moving them between the “user” and “system” space, though these functions are only available on a rooted device.

What we like: Being able to customize both a device’s hardware settings and OS internals with a single app.

Spare Parts Plus!

Spare Parts Plus! is a free app that makes it possible to modify a handful of hidden Android parameters. For example, you can enable or disable the “compatible” display mode, adjust haptic feedback, transitions, and animations. This app can also display a history of battery usage on certain devices.

What we like: The multitude of animation controls.

BusyBox

BusyBox enables many standard Unix commands (like dpkg, ls, mount, su, and so on) on a rooted Android device. Essentially, BusyBox is a collection of useful command-line tools conveniently packaged into a single app.

What we like: Being able to use classic Unix command-line tools in Android.

Superuser

Superuser provides access to the protected areas of your rooted Android device, allowing you to choose the apps allowed superuser (also known as “su”) access to the system.

What we like: Being able to customize the exact privileges for any app.

CatLog

CatLog provides a GUI front-end for Android’s logcat command on rooted devices. This app provides an easy-to-read, color-coded version of the Android system log that is searchable and sortable. You can even save system logs to an SD card and send them as email attachments.

What we like: The color-coded column view and system log export.