IBExpert - IBExpert website
DBeaver - DBeaver - Universal Database Manager and SQL Client.
DataGrip - Tool for SQL and databases
Firebird Maestro - SQL Maestro Group vendors powerful database management and web development tools for MySQL, Oracle, SQL Server, DB2, SQL Anywhere, PostgreSQL, SQLite, Firebird and MaxDB.
HeidiSQL - HeidiSQL is a powerful and easy client for MySQL, MariaDB, Microsoft SQL Server and PostgreSQL. Open source and entirely free to use.
RazorSQL - RazorSQL is an SQL Editor and SQL database query tool for macOS, Windows, Linux, and Mac OS X.