Personal productivity covers your own affairs: notes, tasks and to-dos, calendars, bookkeeping and finance, time tracking, pomodoro and focus timers, knowledge bases, Markdown editors, launchers, plus ebook and novel readers.
The difference from Tools is one of layer. That category holds system-level utilities such as file management, terminals and screen mirroring. This one holds the business of living: capturing, scheduling, measuring, reviewing. A given program may appear in both, and the difference is which door you come in through.
To assemble a complete personal system, pick in the order capture, schedule, execute, review. Notes capture, to-dos and calendars schedule, a pomodoro timer executes, time tracking reviews. If you only have one problem, go straight to the matching subgroup.