YSK about rewards apps that give you cash back for spending

You should check out Drop Rewards and Expense Rewards. Drop gives you cashback for spending at grocery stores and Uber/Lyft. Expense Rewards gives you a few points for every purchase .

If you sign up for them using a referral you'll get more free money ($1 from Drop promo: uakqr and $5 from Expense Rewards promo:FWKUgJ ).