ActiveCoin is the official currency, used in the world of Activy. The only way to collect them is by gathering kilometres and points in the Activy app.
For every kilometre, on an activity longer than 1,5km, you can gain points. Depending on the competition, you will receive a different number of points for each kilometre, streak, a regular bonus or work commute bonus (more about the rules of point-scoring - https://help.activy.pl/en/support/solutions/articles/42000058577-basic-rules-of-scoring-points). Every gained point is converted into ActiveCoins, 1 to 1.
However, if you decide to buy a gadget in the shop or desire a discount, you will pay with an adequate amount of ActiveCoins. After making the purchase, the state of your virtual account will drop, but the points gained will not, neither will your statistics. The purchase only affects the ActiveCoin account.