I had JD on my DroidX, had great success with increasing battery life. I was hoping that HD on my Charge would let me squeeze a little more from the battery, but sadly I found the same thing, the data connection wouldn't turn on. I even tried the option included in JD to toggle the Mobile Data Connection, but no success. I ended up disabling the app and all is working well now. I hope JD developer can work around this issue in a future release.