So I just built my mintyboost and I'm testing it with my Samsung Vibrant. It charges very slowly. I installed this app on my phone that shows me the charging rate of my charger. For my wall outlet it shows a constant 1100 mA. When I use my mintyboost, the mA bounces around. It goes from 0 mA to ~600 mA to ~200 mA then back down to zero. There doesn't seem to be pattern to it either. The numbers are always random, but its 0 at least half of the time. When I use my volt meter to check the voltage of the USB pins, it is at a solid 4.97V and does not fluctuate. I tried using rechargeable 2500maH NiMH batteries as well as brand new duracell AA's.
The app I used is called "CurrentWidget" for android phones.
Any help would be appreciated!