EMITT

QR codes, NFC tags and Flipper Zero files from one app.

Write a payload once, then emit it however you need: a styled QR code, a real NFC tag, or a .nfc file sent straight to your Flipper.

Download · Changelog · Support on Ko-fi

Free and open source · No ads, no tracking, no account · Works offline · 23 languages

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Install

1. Download EMITT-x.y.z.apk from the latest release on your phone.
2. Open it and allow your browser or file manager to install apps when Android asks.
3. That's it. EMITT tells you when a new version is out, and updates install over the top, keeping your library and settings.

Official builds are signed by me, and the About section in Settings says Official build. If it says otherwise, the copy didn't come from this page.

What it does

Create

One editor for text, links, Wi-Fi, contacts, email, SMS, phone numbers, locations and Android apps. Pick an output underneath it:

• QR code: styled, previewed and test-scanned as you type
• NFC tag: proper NDEF records (Wi-Fi tags use the WSC format Android joins automatically), with an optional "also open this app" record. Write it to a sticker or card, or tap Be the tag to make your phone act as the tag itself
• While you style a QR code, a small live preview floats in the corner so you can see each change
• Flipper: an NTAG213/215/216 file the Flipper can emulate, with a random or custom 7-byte UID. EMITT picks the smallest chip that fits.

QR styling and visibility

• Module shapes: square, rounded, dots, fluid, bars, diamond, with adjustable module size
• Eye shapes: square, rounded, circle, leaf, with their own colours
• Flat, linear or radial gradients, and transparent backgrounds
• A centre badge: the EMITT mark, short text, or your own image
• Error correction (L/M/Q/H) and quiet zone controls
• A self-test scan of every code, plus contrast, inversion, border and density warnings, so you know it'll read before you print it
• Full-screen view at maximum brightness for showing codes to other phones
• Export as PNG up to 4096 px, share, or save to Pictures/EMITT

Scan

Camera scanner for QR, Data Matrix, Aztec, PDF417 and common barcodes, or scan from an image. It runs fully on the phone with no Google Play Services. Anything you scan can be opened, copied, saved, or re-emitted as a tag or Flipper file.

NFC tools

• Read any tag: chip type, UID, ATQA/SAK, memory used, every NDEF record, and a raw page dump for NTAG/Ultralight
• Copy a tag's data onto another, erase a tag, or lock it permanently (with a confirmation)
• Import a Flipper .nfc file and write its data to a real tag
• Be the tag: the phone emulates an NFC Forum Type 4 tag, so other phones (Android or iPhone) and Flippers read it like a sticker. A full-screen tag mode keeps EMITT in front, which matters on phones with a built-in tag service (such as Samsung's "Embedded tag"). It gets a random UID each tap, so it can't replace UID-based badges or door fobs
• Phones with a tag built into their NFC chip (common on Android 15 and newer, such as recent Motorolas) answer ordinary readers with that empty tag instead of EMITT, and apps can't change that. EMITT also answers on its own ID, so a phone with EMITT open can always read an EMITT phone
• Testing with a Flipper: to test Write to tag, emulate a blank NTAG on the Flipper (NFC → Add Manually → NTAG215 → Emulate). To read your phone, use NFC → Extra Actions → Read Specific Card Type → Type 4 Tag; plain Read also probes for payment cards, which wakes your wallet app

Flipper Zero

• Pair over Bluetooth (enter the PIN from the Flipper's screen) and see device info and SD card space. Works with renamed Flippers and custom firmware like Momentum; close the official Flipper app's connection first, since the Flipper allows one
• Send files straight to /ext/nfc, list what's there, or make the Flipper beep to check the link
• Convert tags the phone reads into Flipper files (full memory for NTAG/Ultralight; UID/ATQA/SAK for others)
• Or share/save .nfc files and copy them over however you like

Library, widget and tile

Save codes to a library with stars and search. Put any saved code on your home screen as a widget, or pin one to the Quick Settings tile (handy for your Wi-Fi) so it opens full screen in one tap.

Make it yours

Everything lives under the palette icon at the top (Appearance):

• 16 colourways: Mono (the default), Synthwave, Amber CRT, Phosphor, Ice, Ultraviolet, Redline, Vapor, Paper, Solar, Midnight, Sakura, Forest, Ember, Coffee and Glacier, or your own five colours
• 10 background animations: comets, signal, code rain, oscilloscope, radar, dot matrix, circuit, warp, spectrum and pulsar, each with speed, density, intensity and colour controls. Off by default
• CRT scanlines, vignette and flicker; glow; panel opacity and outlines; chamfered, sharp or soft corners; mono or mixed fonts; text size
• 4 control styles for switches, sliders and progress bars: Blade (the default, a sharp hexagon with a hatched half), Segment (LED segments), Bracket (terminal brackets) or Classic
• My themes: save the whole look (colours, background, interface and controls) under a name and switch between your themes in one tap
• 10 launcher icons to match: Amber, Synthwave, Phosphor, Cyan, Mono, Sakura, Redline, Ultraviolet, Paper and Glacier

Languages

English, 简体中文, हिन्दी, Español, Français, العربية, বাংলা, Português (Brasil), Русский, اردو, Bahasa Indonesia, Deutsch, 日本語, Naijá (Nigerian Pidgin), العربية المصرية, मराठी, తెలుగు, Türkçe, தமிழ், 粵語（香港）, Italiano, Tiếng Việt and 한국어. EMITT follows your phone's language, or you can pick one in Settings → Language (on Android 13+ it's also in your phone's per-app language settings). Arabic and Urdu use a right-to-left layout. Flipper menu paths and chip names stay in English so they match your Flipper's screen.

Spotted a clumsy translation? Please open an issue with the language, the screen and a better wording.

Vibration

Pick a pattern (tick, double tap, heartbeat, rising, purr and more, or off) separately for tag writes and reads, for being read as a tag, and for failures, with a strength slider.

Updates

EMITT checks GitHub for new releases when you open it and in the background (every 6 hours to 3 days, your choice). A new version shows a short list of what's new, with Update now and Remind me later. See what's new in Settings → About shows the notes for the version you have. It only asks GitHub's public API for the latest version and sends nothing about you. You can turn this off.

Privacy

EMITT has no ads, analytics or accounts. Scanning, QR rendering and tag work all happen on your phone. The only network request it makes is the optional update check to GitHub.

Permissions are asked for when you first need them: the camera when you open Scan, Bluetooth when you connect a Flipper (Android 11 and older also need Location for Bluetooth scanning), and notifications once on first launch so update alerts can reach you. Saying no only switches off that one feature.

Requirements

• Android 8.0 or newer
• NFC for the tag tools (QR and Flipper files work without it)
• Bluetooth LE for sending to a Flipper

Building it yourself

For developers

You need JDK 17+ and the Android SDK (platform 36).

./gradlew assembleDebug
./gradlew testDebugUnitTest

Release builds look for a signing key in keystore.properties (project root or ~/.emitt-signing/) or the EMITT_KEYSTORE_* environment variables, and fall back to the debug key otherwise.

Where things live:

Path	What
data/	Payload model, Encoding (QR text formats and parsing), Library, Settings, UpdateChecker
qr/	QrRenderer (custom drawing on top of ZXing's encoder), QrDecoder, QrStyle
nfc/	NdefCodec (payload ↔ NDEF, Wi-Fi WSC), TagOps (write, read, erase, lock, NTAG dumps), Type4Tag + EmulationService + Emulator (phone as a tag)
flipper/	FlipperNfcFile (.nfc format v4), FlipperProto (hand-encoded RPC protobuf), FlipperLink (BLE serial, flow control, pairing)
ui/	Compose screens, theme/ (colourways, Backgrounds, CRT overlay)
data/Languages.kt, res/values-*/	Language list and translations; res/xml/locales_config.xml registers them with Android
tools/i18n/	Source text for every language and the script that generates the strings.xml files (see its README)
widget/	Home-screen widget, Quick Settings tile, full-screen code activity
UpdateWorker.kt	Background release check and notification

Support

EMITT is free and open source. If it's been useful to you, you can buy me a coffee on Ko-fi:

Contributing

Bug reports and pull requests are welcome. For tag problems, please include the tag type (from the Tags screen) and your phone model. For Flipper problems, include the firmware version shown on the Flipper screen.

License

EMITT is free and open source under the GNU General Public License v3, with a few additional terms. You're welcome to read the code, learn from it, build it yourself and improve it.

In short, if you share a modified version of EMITT:

• it has to stay open source under the same license,
• it has to keep my credit ("StarlightJulie", linking to my GitHub) in the code, the README and the About screen,
• it has to say clearly that it's modified and not the official release,
• and it needs its own name and icon, signed with your own key. The EMITT name and bracketed-emitter logo are for my official builds.

Please don't re-upload my releases to other stores or sites; link to this page instead.

It's built on these open-source projects:

• ZXing (Apache 2.0): QR encoding and barcode decoding
• CameraX (Apache 2.0)
• Jetpack Compose, Material 3, WorkManager, kotlinx.serialization (Apache 2.0)

The Flipper file format and RPC protocol follow Flipper Devices' public firmware docs and protobuf definitions. Flipper Zero is a trademark of Flipper Devices Inc.; EMITT isn't affiliated with or endorsed by them.

Only write and emulate tags you own or have permission to use.