Dumb phones that can run Airlines apps?

My Iphone 14 has recently been shutting off about 30 seconds (maximum) of being on, and while being a “smart phone” I’ve used it for nothing but text/call and Delta and Alaska airlines apps. Im looking for a dumb phone with 4g network and the ability to run my necessary airlines apps. Ive been looking at phones like the: NUU F4L flip, and the TTFone 990 flip

While I’d like to just get it over with and purchase one of these I’m wondering if there is any catches with these phones that will make me regret purchasing one later or perhaps better options. (Price isn’t a huge factor atp)