There are plenty of fancy audio interfaces available on the market that let you record interviews, podcasts, and other audio programs like a pro. Looking for one that works with your smartphone? The Rode SC6-L can help. It comes with two 3.5mm TRRS jacks for your microphones.
This tiny gadget lets you record 2-person interviews more conveniently. It has a resolution of 24-bit with sample rates up to 48 kHz. The SC6-L works with the RODE Reporter app but is compatible with GarageBand, Voice Memos, and other apps.[where to find it]