Good, could be better.
When you make the images bigger the image quality is not great, which I guess is expected seeing as though Instagram maxes out at 1080. Videos choose when they want to play, its not very consistent and the video player controls look terrible. When scrolling the timeline its a little choppy. Its a pretty decent app but I think the price should be more around the $2-$3 range. The features of it are great, just need to be a little more polished.
Hitekksteff about Photoflow - for Instagram