Single-deck DJ player for Android
DJ Deck turns your smartphone into a single CDJ-style deck with instant response. Plug your phone into a mixer and play with your fingers: CUE, hot cues, loops, pitch and bend, just like on a club player.
Why latency matters
Beatmatching happens in fractions of a second. If there’s slack between your finger and the sound, you’re mixing the app, not the track. That’s why we started with the engine, not the buttons.
The C++ audio engine talks to Android’s low-latency audio API in low-latency / exclusive mode. No third-party libraries, no extra layers.
The audio stream runs all the time. PLAY and CUE don’t have to “wake up” the sound: it’s already running and waiting for your command.
The file is decoded into RAM, so jumping to CUE or a hot cue never waits for storage.
Buttons react when your finger goes down, not when it lifts. Touch event batching is turned off.
Jumps are smoothed over a few milliseconds: no clicks and no added delay.
The engine starts with the smallest buffer and grows it only if audio dropouts appear.
// Actual latency depends on the phone model and its audio path.
Features
Only what you need to mix live, built the way your hands already know from CDJs.
CUE during playback jumps back to the cue point and pauses. While paused, it previews for as long as you hold it. Press PLAY while holding CUE to keep playing. Nothing for your hands to relearn.
An empty pad stores a point, a set one jumps there and plays right away. Points are compensated for output latency, so they land exactly where you heard them.
Set LOOP IN and LOOP OUT by feel, and the length snaps to 1/8 … 32 beats. Exit and reloop with one button.
Lows in red, mids in green, highs in blue. Pinch to zoom from 1 to 32 seconds, slide for precise seeking and cueing, and a full-track overview you can tap to seek.
A raised cylindrical wheel instead of a slider. Ranges of ±8 / ±16 / ±50 %. Key changes with tempo, just like vinyl.
Swipe the pad to nudge the track, with force proportional to your finger’s speed. Sensitivity is adjustable. While paused, it scratches / jogs.
Automatic tempo and grid detection. If the detection gets it wrong, tap TAP and the app finds the exact BPM by analyzing the track. Or mark two beats and it works out the rest.
64 or 128 beats: always see where you are in the track’s structure. It flashes red 8 beats before the phrase ends — time to start the next one.
A corrected grid is saved for good and recognized by the file’s contents, even after renaming. Reloading takes a fraction of a second.
You can start a track about half a second after picking it, while the rest is still decoding.
A smooth fader plus system volume control. If your phone sends too low a level to the mixer, the app warns you and raises it with one tap.
Use cases
A gig on the road, a party, a practice session, or a club where something went wrong.
03 / 04
Acapellas, effects, intros and loops on top of your main mix. Plug the phone into a LINE input and you’ve got one more channel.
B2B
The second DJ brings their own deck in their pocket. No sharing a player or swapping USB sticks mid-set.
LEARN
No SYNC button: just your ears, pitch and bend. You really mix from day one instead of learning to press a button.
BACKUP
The main player froze or the USB stick won’t read — the track is already loaded on your phone, and the dancefloor won’t notice a thing.
Honest about features
Better to find out before installing than in the booth.
Privacy
Everything works offline. Your files never leave the phone.
No sign-ups, logins or subscriptions.
Nothing pops up mid-set.
The app doesn’t request a single Android permission.
FAQ
Use a 3.5 mm cable (mini-jack → 2×RCA or jack) or a USB audio interface into a LINE input on the mixer channel. Don’t use a PHONO input: it’s designed for turntables and will overload. If your phone outputs too low a level, DJ Deck will warn you and raise the volume with one tap.
All the popular formats Android can decode: MP3, AAC/M4A, WAV, FLAC and more. It plays files stored on your phone.
DJ Deck is a single deck that you mix with another player through a mixer. There’s nothing for it to sync to, and beatmatching by ear with pitch and bend is exactly why many people install the app. For that you get precise pitch, finger bend and a beat grid on the waveform.
Pitch works like on vinyl: key changes with tempo. This keeps the sound clean and adds no processing to the audio path.
It depends on the model and its audio path. The engine uses the fastest path the device offers and picks the smallest stable buffer on its own.
Android 9 or newer. The app is lightweight and native, works offline and requests no permissions.
Install DJ Deck, plug a cable into a LINE input and play with your fingers.
Android 9+ · offline · no ads