It really is crazy. Placing my phone on my chest lying down i can clearly see my heartbeat on the graph
good idea https://tautme.github.io/phone-sensors/heartRate.html , try setting it on the ground and see how sensitive it is to foot steps.... or earthquake https://seismosense.com
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good idea https://tautme.github.io/phone-sensors/heartRate.html , try setting it on the ground and see how sensitive it is to foot steps.... or earthquake https://seismosense.com