i.e. can record digitally to an iphone or ipad thru lightning. I'm excluding all-in-ones that already record internally, like the Zoom F6, where such a feature would be redundant
a short list of ones ive tested
dpa MMA-A d:vice
Benchmark ADC1 USB
RME ADI-2 Pro series
Mytek Brooklyn ADC
Motu M series (M2 and M4)
some others which fit the description which i havent tested personally
Sonosax SX-M2D2
RME babyface pro
Apogee Duet
Centrance Mixerface