OziTrackConverter description

Converter for OziExplorer tracks

Converts track into route (OziExplorer *.rte or MapSource *.gpx)

Conversion *.plt в *.kml and vise versa,
Conversion *.plt в *.kmz and vise versa,
Conversion *.plt to *.gpx and vise versa,
Conversion *.plt to OziExplorer route*.rte,
Conversion *.plt to route *.gpx

From Android 4.4.4 and later Google do not permit for third party applications to write to external sd-card. Only to read. So move your source file to internal memory before.