mytaxi's bonuses attempt to achieve the same objective as surge pricing i.e. to improve the efficiency of utilisation of the fleet. Of course, it's not as simple as that as individual drivers chasing bonuses are likely to utilise their vehicles less efficiently than they would in the absence of the same i.e. they will pass street fares to cover app fares. However, on balance, schemes of this nature probably serve to increase supply when demand dictates that increased supply is required as some drivers will adjust their working hours accordingly. Drivers who prefer to work off peak will, of course, benefit from reduced supply during their shifts. Hence it is a win-win-win-win scenario with more money being put in drivers' pockets, increased availability for passengers at peak times, reduced working hours for individual drivers and less folk screaming at Joe Duffy for more taxis/hackneys/limousines/local area taxis.