So many options now, a sampler can fit on a keyboard stand, in a rack or your pocket. Getting one with "the sound" you desire is paramount; if your smartphone can do it better then save your money.
I feel like the 16bit Roland SP202/303/404etc modules are very capable, hifi samplers. Some clunky workflow aside, they do capture impressively detailed high end, but audio that goes into them doesn't "just sound better" when it comes out unless you eq things yourself. They're quite flat/linear in response and I think they greatly benefit from addition of a simple base eq curve with boosted lows and cut highs...like +2db 60hz with wide q or low shelf, and -2dB 12khz high shelf. Mids to taste based on source and purpose. But at this point I feel like the apps for iOS sound just as good when run through the same eq. Even straight from the headphone jack, without an additional audio interface.
8, 12 and the occasional 13bit samplers from the 80s are quite distinct in their sound, largely due to the numerous proprietary converters, algorithms and filter chips that were used. Mostly considered lofi, the sounds they're capable of producing can be massive; even iconic with interesting textures resulting from digital artifacts, particularly from the technique of sampling 33.3rpm records at 45rpm and then tuning down in the machine to stretch limited memory as far as possible. Those limitations are dealbreakers for many and part of the allure to some of us. Cramped sample memory, aging hardware, obsolete i/o and media formats, massive footprint etc...not so much. It's the sound and workflow that keeps people using them even though something like an MPC 5000 or MV-8800 can supposedly "do it all" or whatever. It just doesn't do what I want. AFAIC Plugins and emulators have yet to nail the 12bit-nonlinear thing...but ymmv
