For Simple Views in the Firebird database support full update functionality from the engine (in both server and embedded modes), update/add/delete actions work on the referenced physical table data. 

A Simple View here is defined in the Firebird documentation as an updatable view:

A view will be automatically updatable if all of the following conditions are met:
• the SELECT statement queries only one table or one updatable view
• the SELECT statement does not call any stored procedures
• each base table (or base view) column not present in the view definition is covered by one of the following
conditions:
- it is nullable
- it has a non-NULL default value
- it has a trigger that supplies a permitted value
• the SELECT statement contains no fields derived from subqueries or other expressions
• the SELECT statement does not contain fields defined through aggregate functions, such as MIN , MAX , AVG ,
SUM , COUNT , LIST
• the SELECT statement contains no ORDER BY or GROUP BY clause
• the SELECT statement does not include the keyword DISTINCT or row-restrictive keywords such as ROWS ,
FIRST , SKIP

Base data aware controls do not currently support this ability to update updatable views. Applying update SQL statements directly in the SQL window or in scripted API calls do work in the current builds.

The enhancement request is to add support at a low enough level to support updates to an updatable view via the UI data aware controls.