SQL Terminal provides a command-line interface to SQLite database engine. It allows you to design, populate and query your database in Structured Query Language (SQL). The application is great for studying databases and SQL, but you can also use it to design your database in your mobile and copy the resulting *.db file to your PC (and vice versa).
It's available on Blackberry 10 and Symbian Belle.
For screenshots, go to http://appworld.blackberry.com/webstore/content/28054865/
Note to Symbian users: to install the app, download sql-terminal/symbian/SQLTerm.sis and transfer it to your phone.