I have an '88 FSM on a 512 GB Flash Drive (Thumb Drive). This FSM is a .pdf, but it is unlocked and EDITABLE!
Additionally, the flash drive is configurable to plug directly into your phone as well as into your computer.
This combination means you can take pictures with your phone (before and after) to document your work and put them into your FSM for future reference and be able to find them using the search function built into the .pdf....also zoom, print, make notations, etc.