yWriter 5
yWriter 5 is freeware novel-writing (more strictly: organising) software available from here.
It doesn't have the ideas or brain-storming functionality of some commercial novel-helping apps out there, but that's nothing you'll really miss. What it does have is a logical ability to organise your story into scenes, and I tell you what, it's a great help to overcome continuity issues. One thing I suffer is forgetting what character A did earlier in the novel and having her say or do something plot-breaking a hundred pages on. yWriter 5 will cure this particular affliction.
There's a whole lot more to it and I recommend you watch the Youtube tutorial here.