I built a similar web thing a while back, except it allowed real-time arbitrary slowing down, and at high quality. The issue was that it was a copyright lawsuit

I built a similar web thing a while back, except it allowed real-time arbitrary slowing down, and at high quality. The issue was that it was a copyright lawsuit waiting to happen, given that it ripped the audio from youtube. It works well and is all web based, but I'm too scared to release it to beyond just my friends and myself. The options that won't make lawyers get involved are limited, which is possibly why op did it this way.