All 3Dio microphones use condenser type of microphone capsules. Condenser mics are very sensitive and use low voltage power in order to function and capture intricate sounds. Because of the low voltage and the design of the microphone diaphragm, it means the output volume is also very low. Therefore, ALL condenser microphones require a preamp in order to boost the signal to a volume we can hear. Audio interfaces contain preamps that will boost the signal (they also contain analog to digital converters for computers/smartphones).
To answer the question, an audio interface is required. However, a special audio interface is needed to function properly with a smartphone device because they use different operating systems than a laptop or desktop computer.