dbExpress is an SQLite database implementation.
It allows you to easily create SQLite databases, you can use the Smart Objects module if you need to implement a database very quickly, but you can also implement your own tables (developer edition only).
dbExpress implements CRUD functionnalities (Create Read Delete Update).
The Server Side is powered by PHP/mySQL, so you have to make sure that these tools are available on your Server.
dbExpress / SQLite requires a Web server even during the develoment phase. TB includes an embedded simple Web server that will “simulate” the server side execution, but for large projects, this Web Server may not respond very well, in this case it is recommanded to install a local Web Server on your computer, for example MAMP or the MAcOS Apache Web Server.
A conversion Tool, will be available in the future for converting your project to MySQL.