I have only used it with my iTunes library so I cant speak for WinAmp.
It works well with the basic: Pause, Stop, Next, Previous, and volume controls. I would however like to see a better UI for my iTunes library. It appears as a list of all my songs in alphabetical order. There is no search feature or the ability to select Artists or Albums. I feel this is a basic feature that should have been included. Another feature left out is being able to select the playlist. If youve selected one through the computer you are unable to switch to another one.
However, I do love the fact that it can work off the 3G network and not just a wireless network. Its something that the Remote app should look into.
All in all a pretty decent app. Just update the UI and it will be five stars.
GIork about JumiAmp – Remote Control for iTunes & WinAmp music & video play, v2.10