While users earn free talktime through stock trading game on OFX Trades, users also can earn free talktime through its refer and earn program. Users can invite their friends through WhatsApp, Gmail contacts or share their referral link on social media accounts. You get free PayTM cash for each friend who joins OFX Trades using your referral link. There is no limit on the number of referrals, so you can earn free talktime. The more friends you invite to join OFX Trades, the more Paytm cash you earn.