Some may give a fixed cash reward for each successful referral, while others might give a percentage of the referred user's purchases, or both. Also, some apps might have a tier system whrummy ballere users can advance to receive greater rewards for meeting targets, like referring a specific number of users or a particular amount of money through their referrals. The advantages of the Refer and Earn apps. All things considered, refer & earn apps offer users an easy and efficient way to get compensated for recommending goods and services to their friends and family.