A file with .cell extension is a workbook file created with Cell application. It stores data organized in rows and columns in cells and supports formatting of data such as BOLD, Italic, Underline, etc. Cells comes bundled with Thinkfree Office NEO suite and is similar to Microsoft Excel. Cells lets you save the spreadsheet in other file formats such as XLSX, ODS, and PDF. Workbooks created with cells support several chart types, formulas, and graphs, and are full compatible with MS Excel. Thinkfree suite, in addition to Cell, also contains Word and Show applications that are functionally similar to Microsoft Word and PowerPoint.
CELL File Format - More Information
Cell files are saved to disc in binary file format and its file format specifications are not available publicly.