Soft Arabic Keys is an IME (input method) for entering Arabic Text. When you download the application onto your phone, it appears on the language and settings entry of your settings app. If you Enable it, it will appear as one of your choices of input methods when you long-click on an editable field.
Soft Arabic Keys lets you enter the Unicode codepoints for Arabic letters by pressing on buttons arranged on the screen like an Arabic typewriter keyboard. You can also enter English text by cycling between a total of six different entry screens.
Soft Arabic Keys lets you enter Arabic text, but for Android versions before Honeycomb (Android 3.0) the app you are using the text for is in charge of showing it correctly, and many do not. If your phone does not have Arabic fonts loaded, you will not be able to read the characters entered on the screen, even though they are internally correct. (Nor will you be able to read the characters on the keyboard buttons, because they use system fonts.) Soft Arabic Keys uses the plane 6 Unicode Arabic codepoints, but even if your phone has an Arabic font installed, these codepoints show on the screen as disconnected characters unless the app in which they are used is Arabic-aware.
Soft Arabic Keys has buttons for moving the cursor left and right and extending the selection left and right, for people who prefer using the keyboard rather than clicking on the text itself.
Soft Arabic Keys is based the Android Sample Soft Keyboard. The sources are available from firstname.lastname@example.org.