Yes, it is possible to use a smartphone to record low-frequency waves, depending on the capabilities of your smartphone and the specific frequency range you are interested in capturing.
Smartphones typically have built-in microphones designed to record human speech and other sounds in the audible frequency range (20 Hz to 20,000 Hz). However, they may not be optimized for capturing very low-frequency waves, such as those below 20 Hz.
If you're trying to record low-frequency waves, such as infrasound or extremely low-frequency (ELF) waves, the built-in microphone of a smartphone may not be sensitive enough to detect and accurately record those frequencies. In such cases, you might need specialized equipment, such as a dedicated microphone or a low-frequency data acquisition system, that is specifically designed for capturing low-frequency waves.
It's worth noting that even if your smartphone's microphone can pick up low-frequency waves, the quality and accuracy of the recordings may vary depending on the smartphone model and its microphone's specifications. Additionally, external factors such as background noise and interference can affect the recordings.
If you have specific requirements for recording low-frequency waves, it is advisable to consult with experts or professionals who specialize in the field of acoustic measurements or data acquisition to ensure you use the appropriate equipment for your needs.