TCR files are text files carrying nametag Text compression for Reader. It is file format especially created for devices called Psion Organizer developed by Psion PLC company. The main advantage of this file format is specific compression, which is approved by much better compression ratio when it is compared with PDB file format, which was the biggest rival of this file format in the past.
The most used program to open this format is probably EBook for EPOC, which is freeware application serving as e-book and e-text reader. This reader supports PalmDoc format and even other file types. But especially it is developed for TCR format. Outside of this application, there are two others. First is CoolReader and her equivalent is STDU Viewer.