1. Yoolki Arabic Keyboard – Firefox Addon on Sony Ericsson Xperia PLAY R800i (SE Zeus). Just open right click any text field and select "Write Arabic here" to write in Arabic using an English keyboard. The add-on can transliterate your English letters (ex: akala el waladou el touffA7ah to أَكَلَ الوَلَدُ التُفاحَة) or translate English to Arabic using Google translate. (ex: The boy ate the apple). Here this link :

http://supportscentre.com/free-download-yoolki-arabic-keyboard-firefox-addon-for-android.html

Note : You must have software requirement for addon : Fire fox mobile

2. Download here Arabic Language Pack for AnySoftKeyboard Sony Ericsson Xperia PLAY R800i (SE Zeus). Here this link :

http://supportscentre.com/arabic-language-pack-for-anysoftkeyboard-version-20110127.html

3. Download Arabic soft Keyboard for Sony Ericsson Xperia PLAY R800i (SE Zeus) Smartphone. Here this link :

http://supportscentre.com/arabic-soft-keyboard-abdullah-bahitham.html

4. Or find out more application from google play (android market) :

https://play.google.com/store/search?q=arabic+keyboard&c=apps