plOpen...

Data files created by typical EPOC applications and typical data files (text files, web pages (.HTML), files containing graphics, etc.) can be open on palmtops with EPOC system. Data files created by EPOC applications contain information which application they were created with and which application can be used to open them. Typical data files do not contain this information, EPOC system recognises them using MIME recognisers and opens them with applications that use a given MIME type. This works properly when only one application using a given MIME type is installed.
When there is more than one application using the same MIME type, the user can not choose which application will be used to open the file.

plOpen allows to link the given data type to one application or even choose any other application, e.g. text files are normally open with the Web application, after installing the Editor application (word processor) it can also be used to open text files - plOpen allows to link text files (plain text) with the Editor or Web application (and to change it at any time). 
plOpen also allows to add new types based on file name extensions and to link them with any application.
If the user tries to open a file of an unknown format, plOpen will propose to open the file with a chosen application or to link all the files of this type with a chosen application.