Doesn’t Sapphire have a $95 annual fee, waived the first year?
Chase Freedom used to be a good card, but for me its current scheme of a 5% rebate in varying categories every quarter, 1% everywhere else, is just too much of a bother. For instance, you can get a 5% rebate on Amazon, but only in January-March and only if you remember to sign up for it that year. From July-September last year, the 5% discount was only for shopping at Kohl’s.
For the OP I recommend Sallie Mae Barclays MasterCard, which offers a 5% cash rebate on the first $250 spent each month at grocery stores, 5% on the first $250 spent each month at gas stations, plus 5% on the first $750 each month at bookstores. Everything over that limit or at other store types gets you 1%. You can get it as a statement credit (or to pay down a Sallie Mae loan if you have one).
Amazon also has a decent card offered through Chase, with a 3% rebate at Amazon, 2% at restaurants and drug stores, 1% elsewhere, that’s good on Amazon.
But more important than which card is developing a system so you never ever pay interest, and never buy something you can’t pay for at the end of the month. If you can’t manage that, a debit card will let the bank do it for you, but it’s much better to do it yourself. Such a system might mean entering every card purchase into her smartphone, until she gets an idea of how much her regular purchases run each month, and can mentally put that money aside.
If she really needs to carry a balance month to month, the list of “best cards” becomes completely different. Any rewards will be quickly swamped by the interest rates and fees.