How to open .GF files on Android
To open .GF files on Android, android does not commonly include TeX/METAFONT utilities; move the .gf file to a desktop system with TeX Live to inspect it with gftype or convert it with gftopk.
Step-by-step instructions
- Android does not commonly include TeX/METAFONT utilities; move the .gf file to a desktop system with TeX Live to inspect it with gftype or convert it with gftopk.
Recommended software
- Acode
- QuickEdit
- JSON Genie
Alternative methods
- Open .GF in a browser-based viewer if desktop apps fail.
- Try opening .GF on Android with a secondary app to rule out app-specific issues.
- Convert .GF only with trusted tools when direct opening is not possible.
Common issues
Double-clicking the .gf file does nothing or opens the wrong app
.gf is a specialized METAFONT bitmap output and is not typically associated with desktop GUI apps.
- Use command-line tools: run gftype to inspect the file, or gftopk to convert it to .pk.
- If you need the font for TeX, ensure your TeX distribution is installed and its binaries are on your PATH.
TeX/DVI tools cannot use the font (missing .pk)
Many workflows expect PK as the canonical TeX bitmap font format; GF is often an intermediate output.
- Convert the GF file to PK using: gftopk yourfont.gf yourfont.pk
- Confirm the PK font is placed where your TeX/DVI environment searches for bitmap fonts.
gftype/gftopk reports errors or the output looks corrupted
The GF file may be incomplete, not actually a GF file, or produced by a mismatched/incorrect METAFONT run.
- Verify the file really is METAFONT output (often named like NAME.NNNNgf) and was transferred/downloaded completely.
- Regenerate the font with METAFONT if you control the source, then re-run gftype or gftopk.
Security note
GF files are bitmap font data and do not contain macros/scripts in the way TeX input files do, but opening malformed files in parsers/converters can still trigger bugs; only process .gf files from sources you trust.