MariaDB is described as 'Backward compatible, drop-in replacement of the MySQL® Database Server. It includes all major open source storage engines' and is a very popular relational database in the development category. There are more than 50 alternatives to MariaDB for a variety of platforms, including Windows, Linux, Mac, Self-Hosted and Web-based apps. The best MariaDB alternative is SQLite, which is both free and Open Source. Other great apps like MariaDB are PostgreSQL, MySQL Community Edition, MongoDB and Microsoft SQL Server.