If you're a frequent Frontier Airlines flier, the FRONTIER Airlines World Mastercard® could be a good choice. It offers generous rewards on Frontier purchases, a substantial welcome bonus and travel perks like free checked bags, priority boarding and an annual flight voucher.
However, the card does come with a $99 annual fee after the first year, and your miles will expire if you don't use your card for six months. Plus, your redemption options are limited to Frontier flights, which might not appeal to those seeking more flexibility. This card could work for dedicated Frontier fans but less so if you prefer broader redemption options.