gretl is described as 'Is a cross-platform software package for econometric analysis, written in the C programming language that can import SPSS data files'. There are more than 10 alternatives to gretl for a variety of platforms, including Windows, Mac, Linux, Xfce and Microsoft Office Excel. The best alternative is R (programming language), which is both free and Open Source. Other great apps like gretl are RStudio (Free, Open Source), PSPP (Free, Open Source), RKWard (Free, Open Source) and IBM SPSS Statistics (Paid).
PSPP is a free software application for analysis of sampled data. It has a graphical user interface and conventional command line interface. It is written in C, uses GNU Scientific Library for its mathematical routines, and plotutils for generating graphs.
The IBM SPSS software platform offers advanced statistical analysis, a vast library of machine-learning algorithms, text analysis, open-source extensibility, integration with big data and seamless deployment into applications.
Deducer is designed to be a free easy to use alternative to proprietary data analysis software such as SPSS, JMP, and Minitab. It has a menu system to do common data manipulation and analysis tasks, and an excel-like spreadsheet in which to view and edit data frames.
SOFA Statistics is an open-source statistical package, with an emphasis on ease of use, learn as you go, and beautiful output. The name stands for Statistics Open For All. It has a graphical user interface and can connect directly to MySQL, SQLite, MS Access, and MS SQL Server.