Best Transcription Apps for iPhone & Android (On-Device, No Upload)

Searches for a transcription app have grown more than tenfold in five years, and the app stores have filled up to match. Most lists rank them by accuracy. That matters, but a more useful first question is simpler: does your audio leave the phone? Once you answer that, the field narrows to a handful of apps worth your time.

We make BlackBox, so treat this as informed rather than neutral. Every claim about another app below comes from its own store listing or help pages, linked in the sources at the end.

Quick verdict. To transcribe things you record yourself without uploading anything: Apple Voice Memos on a recent iPhone, Google Recorder on a Pixel, or BlackBox on any iPhone or Android phone, especially for long or all-day recordings. To transcribe files you already have, on-device: Aiko (Whisper). For team notes, summaries and human-checked transcripts: Otter or Rev, both cloud services.

What to check before you pick

For how the on-device approach works, see on-device transcription explained.

The apps at a glance

"Not stated" means the listing or help page doesn't say. We don't fill gaps from memory.

BlackBox — for long and all-day recordings

We make BlackBox; read this section knowing that. BlackBox is a background recorder first: it records all day or on weekday and weekend schedules, saves each hour as its own file, and transcribes on the phone.

Strengths

• On-device transcription with timestamps and speaker labels, so a two-hour meeting becomes searchable text with "who said what", without an upload.
• No account. Recordings and transcripts stay on your phone unless you export them to a folder you choose.
• Built for long audio. Hourly files and a daily timeline mean a full day of recording stays manageable, and you can jump to any moment.
• Works on iPhone and Android, with the library behind Face ID, fingerprint or a passcode.

Weaknesses

• No live captions. Transcription runs after recording, not while people talk.
• No AI summaries. You get the transcript, not a summary or action items. (You can paste a transcript into an assistant you trust; see summarising transcripts with AI.)
• Transcribes its own recordings only. It doesn't import files you made elsewhere.

Best for: lectures, meetings, interviews and full days you want to search later, kept private.

Apple Voice Memos — already on your iPhone

Apple's guide says Voice Memos can transcribe speech while you record or after, on iPhone 12 or later, in English (all variants), Spanish, Portuguese, Italian, French, German, Japanese, Korean, and Simplified and Traditional Chinese. It isn't available in every country or region. You can search titles and transcripts, copy the text, and older recordings are transcribed automatically when opened.

Strengths: nothing to install; live transcript view; transcript search jumps the playhead to the word.

Weaknesses: iPhone only; no scheduling or all-day mode; exporting the text means copying it out. More detail in converting voice memos to text.

Best for: iPhone owners transcribing short recordings they start and stop themselves.

Google Recorder — the Pixel standout

Google's listing says Recorder "automatically transcribes and labels" what you record, so you can search it, and it can summarise. Google's help pages put speaker labels on Pixel 6 and later, and the app is for Pixel phones only.

Strengths: excellent live transcription and search; speaker labels on newer Pixels.

Weaknesses: Pixel-only, no iPhone version; built around recordings you start yourself. We compare it in detail in BlackBox vs Google Recorder.

Best for: Pixel owners.

Aiko — Whisper on your device, for existing files

Searches for a Whisper transcription app have taken off. Aiko is the cleanest example: its listing says transcription is "powered by OpenAI's Whisper running locally on your device. Nothing leaves your device." It supports 100 languages and exports subtitles.

Strengths: on-device, wide language support, good for transcribing files you already have.

Weaknesses (from its own listing): no live transcription, no speaker detection yet, and on iPhone the app has to stay open while it transcribes. It favours accuracy over speed.

Best for: turning an existing recording into text privately, in almost any language.

Otter — cloud meeting assistant

Otter's listing describes live transcription in English, Spanish and French, speaker labels, summaries, an AI chat and action items, and automated notes for Zoom, Google Meet and Teams. It needs an account, and transcription needs an internet connection.

Strengths: live notes, team sharing, summaries.

Weaknesses: your audio and transcripts are stored in Otter's cloud; three languages. See BlackBox vs Otter and Otter alternatives.

Best for: teams that want shared, summarised meeting notes and are fine with cloud processing.

Rev — AI transcripts plus human ones

Rev Record & Transcribe records, transcribes live with AI, and lets you order human-verified transcripts, with files synced to your Rev account. It also offers AI templates for summaries.

Strengths: the human option, when a transcript has to be right for legal, research or media work.

Weaknesses: cloud-based and account-based; no current Rev recorder on Google Play in the US when we checked. See BlackBox vs Rev.

Best for: professional transcripts you need to stand behind.

Already have a file? Two private options

• Aiko imports a file and transcribes it on-device.
• Our audio to text tool runs a Whisper model inside your browser, so the file isn't uploaded. Good for a one-off.

For the full set of methods, from dictation to cloud services, see how to transcribe a voice recording.

How to choose

• Privacy is the priority, and you record it yourself → Voice Memos (iPhone), Google Recorder (Pixel), or BlackBox on any phone, especially for long recordings.
• You need speaker labels without the cloud → BlackBox. On a Pixel 6 or later, Google Recorder also labels speakers. More in transcription with speaker labels.
• You have files in many languages → Aiko.
• You need summaries and team sharing → Otter.
• You need a human-checked transcript → Rev.

Recording other people carries legal duties that no app handles for you. Check the consent rules where you are first: is it legal to record audio?

Head-to-head comparisons

• BlackBox vs Otter.ai
• BlackBox vs Rev
• BlackBox vs Google Recorder
• BlackBox vs Apple Voice Memos

See all comparisons.

The bottom line

The best transcription app is the one whose trade-off you can live with. Cloud apps buy you summaries and collaboration with your audio. On-device apps keep it, and for most personal recording that is the better deal. If you want to record long stretches, meetings or whole days and get searchable, speaker-labelled text without anything leaving your phone, that is what we built BlackBox to do, on iPhone and Android.