Psion OPO/OPA

File Format
Name	Psion OPO/OPA
Ontology	Electronic File Formats Executables Psion OPO/OPA
Extension(s)	.opo, .opa, .app

OPO (OPL Object, Psion OPL Output) is an executable format used on Psion PDA devices. OPO files are usually created by compiling programs written in the OPL programming language.

There is an OPA variant format, which can also contain embedded resource files. The embedded files usually include an icon in Psion PIC format.

See also:

• Psion IMG/APP (similar formats)
• EPOC/Symbian executable (successor formats)

Identifiers

The usual file extensions are .OPO and .OPA. We've observed .APP as well, though that's more commonly used for Psion IMG/APP format.

Identification

OPO and OPA files begin with the ASCII signature "OPLObjectFile**".

Specifications

• http://www.davros.org/psion/psionics/opo.fmt

Software

• http://www.project-atlantis.co.uk/download.html → OPL Info (OPO executable that displays information about OPO executables)
• Deark (can extract embedded files)

Sample files

• http://cd.textfiles.com/pdasoftware/PSION/ ... (*.OPO, *.OPA)
  • CONVERT.APP, RISK.APP - Examples with .APP extension
• dexvert samples — executable/psionOPL