video with app like win movie maker?

[katycoachswim]

I'd like to use a Samsung Galaxy 10.1 (not purchased yet) to take HD video and then immediately play it back at slower than 1x speed (variable) for athletic feedback. Can anyone suggest a solution or direct me to a better product and app? I can wait for a better product, would really like USD/HDMI/microSD slot. Looks like "tablet wars" launching, should I wait?

TIA, looking fwd to being a member!