I know way more advanced and feature-rich solutions exist but I’m not sure if they have the feature of a phone call being the trigger. Probably someone will find this one useful for DIY projects or something.
Warning: using this app for creation of explosive devices and other illegal purposes is not recommended and may result in legal trouble. Make sure to check local laws before creating any automated device.
this plus the motion project plus a bunch of old unused androids equals free home security cameras w remote check in. thank you for making me aware