Awesome tool which automatically manages your PPC campaigns on Amazon. All you need to do is set your desired ACOS %, and it will optimize the campaigns for you.
Amazon provides only two months of data in their downloadable sponsored ads reports, so I use this app to collect more historical stats on each keyword. I can now make an easier decision to pause or continue running a keyword, because I have more statistically significant amount of impressions and clicks.
Overall, it's a nice and polished web app - I really enjoy using it.