The rates are per country and can change at any time. Current rates are:
USA: $3 per installation, *launch promotional rate ($0.03 upon installation, $0.099 per active day)
United Kingdom: $1 per installation ($0.01 upon installation, $0.033 per active day)
Turkey: $1 per installation ($0.01 upon installation, $0.033 per active day)
Rest of the world: $0.50 per installation ($0.005 upon installation, $0.0165 per active day)