App that records audio 24/7 in background and saves it

Question

I'm looking for an app that does the following:

1. Continuously record audio 24/7 in the background or when the sound is above a threshold
2. Writes a file with the timestamp for that file (e.g. 2020-09-01 19:00:00)
3. Record both ends of the phone call
4. Save a transcription in a text file with timestamps so I can quickly search the text file for the part I am looking for.
5. Allow for using Google Assistant voice command "Hey Google"

With a 256 GB SD card, I could record 72 days worth of audio (using mp3). Of course, battery life is some concern.

I know about Rewind, Alibi, Echo, SnipBack and Cogi. These apps only record the past several minutes and will only save with user interaction.

Proof Recorder and Voice Activated Recorder look like a good start. Is there something better?

I realize that it can be illegal to record without others knowing. It depends on the local laws. For my locale, it is legal to record so long as I am present.

Currently, I start an audio recorder and then later stop it. I would like to skip the manual steps and having to remember.

I realize this is a tall order. There may be apps that do not have all of these features. As a bare minimum, the app should record audio and save it to files without my interaction.

Answer 1

Haven should meet your requirements (a slightly newer version can be found in my repo. It won't write 24/7 – but listen to its environment 24/7, then write when "anything moves" (motion, sound, vibration & light detection trigger recording). It will record audio and make photos.

The app is available for free at Google Play (first link) and via my F-Droid repo. The project behind it, Guardian, focuses on privacy and security. The app was developed to protect personal spaces and possessions without compromising privacy. From the original description:

Haven turns any Android phone into a motion, sound, vibration and light detector, watching for unexpected guests and unwanted intruders. We designed Haven for investigative journalists, human rights defenders, and people at risk of forced disappearance to create a new kind of herd immunity. By combining the array of sensors found in any smartphone, with the world’s most secure communications technologies, like Signal and Tor, Haven prevents the worst kind of people from silencing citizens without getting caught in the act.

IIRC, recordings can even be uploaded automatically. SMS notifications had to be removed due to Google restrictions; might well be the version in my repo still has them, as it doesn't come from Google but from the devs' repo.