The rides will be billed according to the minutes you use. So you only pay for emmy if you use emmy. One minute of riding starts at 0.30 EUR and one minute in parking mode costs 0.13 EUR. You can find more information here: Prices.
There is currently no fee for registering with emmy. However, you will receive 25 free minutes directly. Please note! All free minutes that you receive via a promotion code or in the form of a credit are valid for 6 months after redemption.