ISO Tool v1.91 is released. ISO Tool is a handy homebrew application that lets you manage and backup your UMD's straight from your PSP. ISO Tool completes by Japanese Developer Takka.

ISO Tool v1.91 Changelog:
[NEW] HBL at startup Fixed the error reappears PRX read (FW 5.51 or higher will have to come out)
[NEW] HBL make changes when using the View menu,
[BUG] HBL Fixed a freeze when using at the end (if you return to exit the menu HBL, HOME Back to the case of the XMB)
[BUG] When you start "ms0: / test" was to remove fixed (remains of debugging)
[BUG] EBOOT.OLD fixed conversion was not possible to
[NEW] 5.50GEN-D3/D2 when patched in the farm system with "5.50GEN-pD ~" was to make the show
[NEW] 5.50GEN-D2 system supports plug-ins

Download: ISO Tool v1.91
Source: Here