The card view has a relatively high number of commands, nearly all of them contained in nested menus. It takes three taps to issue one of those commands, and some "mental work" to locate each of them in the menu hierarchy. If you need a command repeatedly, which probably happens quite often, this is far from ideal.
That's why MoStacks implements a command history: It tracks every card view menu command that you issue and remembers it in a command history.
The second-to-last "mini button" in the navigator brings up a popup menu that contains this command history, with the latest command on top:
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It so happens that the first menu entry with the latest command will include the area of the "mini button" to tap, so a double tap results in a repeat of that command!
Note that the command names are slightly modified to make them recognizable outside the context of their menus. E.g. the various "Info" commands (stack info, card info, field info, etc.) within their own menus can be written simply as Info, but in the repeat command popup menu they need a qualifier.