As you'd be recording all of your conversations, this is illegal under some legislations, unless all your conversation partners agree with being recorded/their convos being stored.
I mentioned it in another reply but this is discussed in The Every by Dave Eggers, there is essentially an entire area of San Francisco that is deliberately kept free of any and all devices that can record A/V and in order to enter you have to deposit your phone and be wanded to detect surreptitious recording devices.