CallVault

Records your calls, transcribes them, and summarises them — all on the phone itself.

Free, no ads, no accounts. Nothing leaves your phone unless you switch on Drive backup.

Recording call audio needs shell-level privilege. CallVault gets it one of two ways — pick either in the setup wizard, and switch whenever you like:

Compare the two ↓

CallVault is a fork of ShizuCallRecorder (Copyright © kitsumed (Med)), re-architected to run self-contained over embedded ADB, so it no longer needs Shizuku — and still runs through it, as a second mode, if you prefer. It is a modified, independent version — not endorsed by or affiliated with the original author. See NOTICE.md.

What it does

• 🎙️ Phone calls, both sides — automatically, or ask-me-each-time.
• 💬 App calls — WhatsApp, Signal, Telegram and others, and you pick which apps get recorded. Opt-in, experimental.
• 🎛️ Controls while you talk — pause, resume, stop, or mark a moment to find again later. On phone calls and app calls alike.
• 🔗 Merge calls that were one conversation — a call drops and you ring back; join them into one recording, in the order you choose. Lossless, and un-mergeable afterwards.
• 📝 Transcripts — 13 languages, written on the phone.
• 🧾 Summaries — intent, key points, decisions, action items.
• 🗣️ Speaker labels — who said which line, on phone calls.
• 🔎 Search — a contact on the Recordings page, a word across transcripts or summaries, right on the page.
• 🏷️ Tags and stars — label a call, star the ones worth keeping, filter the list by either.
• 📤 Export a transcript as text, Markdown, SRT, VTT or JSON.
• ▶️ Playback with a waveform you can scrub, plus a note per call.
• 🔒 App lock — your phone's own unlock, required before any recording or transcript is shown. Optional.
• ☁️ Google Drive backup — optional.
• 🧹 Housekeeping — delete recordings past a chosen age, cap how much space they may use, or drop very short ones. All off by default, and a starred recording is never deleted automatically.
• 🔔 Says when it has stopped working — if recording can't start after a reboot, or recordings stop reaching Drive, it tells you rather than leaving you to find out from a call that is not there.
• 🔄 In-app updates — checks GitHub, verifies the signature, installs on your tap. Never on its own.

Recordings are Opus in an .ogg file at 24 kbps by default (AAC/.m4a also available, 8–128 kbps), saved to a folder you pick and can open in any other app. CallVault can also write BCR's metadata file beside each recording — off by default — so tools built for BCR, such as bcr-gui, can read your calls' details.

Recordings	Playback & summary	Transcript

Search	Transcription settings	Settings

Transcripts and summaries

Both run on the phone, on the CPU, with no account and no network.

Transcription uses whisper.cpp. Two models — 190 MB, or 574 MB for better quality — downloaded once over Wi-Fi.

Summaries use llama.cpp with Google's Gemma. It is a 2.6 GB download and needs a similar amount of memory to run, so it wants a recent phone; CallVault states the cost before it downloads anything.

Speaker labels come from the call's own two channels, not from a voice model, so they cost nothing extra. One tap tells CallVault which side is you, and it renames every past phone call too. App calls stay as Speaker A and Speaker B.

What leaves your device

CallVault reaches the network in three places, and nowhere else: GitHub, to check for a new release (on by default, roughly daily); Hugging Face, to download a model you asked for; and your local network during pairing, to find the phone's own debugging service. Drive backup goes through Android's own file picker using the Drive app already on your phone — there is no login in CallVault, and it never talks to Google's servers itself.

Requirements

• Android 11+, 64-bit ARM (arm64-v8a). On Android 11 the screen must stay unlocked during a call.
• Developer options stay on — in built-in ADB mode. Turn them off and recordings come out empty; the Home screen warns you.
• Room for a model if you want transcripts (190 MB or 574 MB) or summaries (2.6 GB, plus the memory to run it).

Two ways to run it

Built-in mode is CallVault's own, and the default. It pairs once, on the phone, and needs no second app at all. It is the default because it can do more, not because Shizuku is an afterthought.

Already running Shizuku? CallVault supports it directly. Choose Shizuku mode and there is nothing to pair, no wireless debugging to switch on, and CallVault starts no debugging of its own — it borrows the privilege Shizuku already holds. Phone calls record, and everything that happens afterwards — transcripts, summaries, search, tags, playback and export — is identical. What differs is capture-side only.

Switch whenever you like; any setting a mode couldn't honour comes back when you switch away. The table is the honest difference between the two.

Install

Download CallVault.apk from Releases, or add the repo to Obtainium for automatic updates.

CallVault can't be on Google Play — Play bans both call recording and the privilege mechanism it depends on. F-Droid is planned.

Then open it and follow the setup wizard: accept the disclaimer, grant permissions, pair once (or pick Shizuku), and choose where recordings are saved.

Pairing, step by step

1. Turn on Wireless debugging — Settings → System → Developer options. CallVault detects it and offers a shortcut if it's off.
2. On CallVault's Permissions screen, tap Pair. It opens the Wireless-debugging screen and waits.
3. Tap Pair device with pairing code and type the six digits into CallVault's notification.
4. Paired ✓ — tap it to go back and finish the wizard.

If a recording stops when you lock the screen, set Default USB configuration to Charging only. CallVault offers this during setup and from Settings.

The two debugging switches

Both live in Developer options, and they do different jobs. You don't need both on all the time.

• Wireless debugging is how CallVault gets in. It uses it to pair, and to start its recorder again after a reboot or an update. It only works on Wi-Fi — Android refuses it otherwise, asks you once to trust each new network, and turns it off when Wi-Fi drops.
• USB debugging keeps the recorder alive away from Wi-Fi. No cable is involved. With it on, CallVault can switch Wireless debugging off after using it, and recording away from Wi-Fi becomes possible.

If you switch Wireless debugging off yourself, CallVault leaves it off. The notification says recording is paused and has a button to turn it back on. If you'd rather CallVault switch it back on for you, turn on Keep Wireless debugging on for recording in Settings ▸ Experimental (you're also asked during setup).

In Shizuku mode, Shizuku runs inside the same debugging service, so anything that restarts it stops Shizuku: turning USB debugging off, or arming recording away from Wi-Fi in built-in mode. Start Shizuku again from its app — CallVault tells you when that's needed and reconnects on its own once Shizuku is back. Shizuku started after USB debugging is already off keeps running.

On OPPO, OnePlus and Realme phones

ColorOS, OxygenOS and Realme UI refuse ADB permission grants out of the box. CallVault pairs, and then the privilege it needs is quietly denied — so recordings never start. This affects Shizuku mode too; Shizuku reports it as "the permission of adb is limited".

One switch fixes it, and it is not in an obvious place:

1. Open Settings → System → Developer options.
2. Scroll to the bottom of the Apps section — it is the last item there.
3. Turn on Disable system optimization. Older builds call it Disable permission monitoring.

Can't see it? It is hidden in some translations, which is why people conclude their update removed it. Set the phone's language to English, turn the switch on, then set the language back — it stays on.

Flip it before pairing. If you already paired, restart CallVault afterwards: a session that started earlier keeps the permissions it had at the time.

Get in touch

Join the CallVault group on Telegram — the quickest way to ask a question, report something odd, or hear about a new build. Bug reports are still welcome as GitHub issues, which is the better place for anything that needs a log attached.

What's next

• Speaker names for app calls — WhatsApp and Signal transcripts still read "Speaker A"; phone calls already get real names.
• F-Droid — so updates arrive through a store rather than a download.

Building from source

git clone --recursive https://github.com/madkongo/CallVault.git
cd CallVault
./gradlew assembleRelease

Needs JDK 17, the Android NDK (27.2.12479018) and CMake — the transcription and summary engines are built from source. Without a keystore at signing/callvault-signing.keystore the release APK builds unsigned; sign it yourself before installing.

Code shrinking stays off: the privileged recorder is launched out-of-process by app_process from a class named in a string, so R8 cannot see it as reachable and strips it.

Credits & attribution

CallVault is a modified fork of ShizuCallRecorder by kitsumed (Med); the original project's name, trademarks, and logos are the property of their owner and are used here only for this required attribution. The ADB pairing/mDNS code is adapted from RikkaApps/Shizuku (Apache-2.0).

Built on the work of:

• scrcpy — the fallback audio-capture server
• libadb-android — the embedded ADB client
• whisper.cpp and llama.cpp — on-device transcription and summaries
• Gemma by Google — the summarisation model, Apache-2.0, downloaded on request rather than bundled

License

Licensed under the GNU General Public License v3.0. ⚠️ Additional Terms under GPLv3 Section 7 apply (at the end of the license file), including trademark protection and the mandatory fork-attribution requirements that this project complies with.

CallVault is not affiliated with, endorsed by, or supported by kitsumed/ShizuCallRecorder, Shizuku, scrcpy, or Google/Android. "Android" is a trademark of Google LLC.

Disclaimer

Recording phone calls may be subject to complex and varying laws in different countries and jurisdictions. You may need consent from all parties before recording. The developers and contributors are not responsible for any misuse or legal consequences. Learn more: Telephone call recording laws. This is not legal advice — consult a legal professional for your situation. It is your responsibility to verify that CallVault's behavior on your device complies with your local laws, and to stop immediately any activity that would constitute a legal infraction.

2.4.4 was published briefly and pulled the same day after a false "a call was cut off" message; 2.4.5 is 2.4.4 plus that fix, two new languages, and a vivo tip.

Added

• New languages — Persian (فارسی) and Arabic (العربية), with right-to-left layout throughout (Settings → Language).
• Transcripts beside recordings — optionally save the transcript, notes and summary as a .md file next to the audio, same name, same folder — so copying the folder to a PC carries the text too (off by default).
• More filename templates — contact- and number-first orders, to group a PC folder by who the call was with.
• Export/import settings — save your preferences to a file and restore them on a new phone (device-specific setup is left out).

Changed

• vivo tip — when only your side of an app call records, CallVault points you to vivo's own "In-app call recording" setting instead of blaming the other app.

Fixed

• Fixed — no more false "a call was cut off" message for a call that actually recorded fine.