Once you’re logged into WEBTOON, you can purchase Coins directly from the Coin Shop. The link to the Coin Shop is at the top right of the ‘My Series’ Screen. You can also access the Coin Shop by tapping the episode that you’d like to unlock on series available through Fast Pass or Daily Pass.
If you are using an iPhone, you can also use the guest-user feature to purchase Coins. However, please note that Coins purchased using iOS guest login are not saved to a WEBTOON account, and therefore may be lost if you log out. Additionally, user support may be limited without a WEBTOON account.