It's easy to earn free credits or to buy them on FreeTone!
As stated in the app description you need to earn free credits to call landline or mobile numbers in many Countries. Receiving calls or calling your freeTone friends won't affect your credits.
To earn credits :
From the left bar menu, tap "Earn credits".
Pick one option :
1 - You can earn free credits by downloading apps or signing up for web services
2 - You can earn free credits by watching a video
3 - You can buy cheap credits
4 - You can earn credits by inviting friends
Remember, you don't need "credits" to call or text FreeTone users, so invite your friends!