I bought this app for just under 5 euro, I then purchased a booster of 15x.after a couple of hours I done the math and it did not justify paying the money .I bought the booster for 50 euro,if I had just bought 50 euro bit coin I would own triple the amount of bitcoin,compared to the amount I would own after 1 month mineing with a 15x booster.so do not waste money on the boosters.even if I had it running 24 hours a day it still would not equate to 50 euro worth of bit coin.not hard to understand