“Wir lassen dich nicht allein”
Not even while practising: cori's official 6K practice room, as an app and in the browser
Your children practise all the songs of the 2027 season on their own at home, with video, chapter markers and follow-along lyrics. Free for every participant.
👧 100,000+ children
🏟️ 7 cities in Germany & Austria
🎤 6,000 voices per concert
✓ Free for participants
The 6K practice room, as an app and in the browser
In the months before the big concert, your children learn a complete repertoire of pop, classical and folk songs. With cori, the 6K practice room goes mobile: children sing, dance and practise independently from home. Anytime, anywhere, with zero effort for you as teachers.
Learn more about 6K UNITED! →
Launched in 2026, ready for 2027
The joint launch
6K UNITED! and cori launched their partnership at the end of the 2026 season. Thousands of children practised their 6K songs with the app for the first time, and their feedback shaped the 6K area.
Ready for the new season
For “Wir lassen dich nicht allein”, everything is on board: the 6K area in the app and in the browser, classrooms and appointments for teachers, and every song with chapter markers and follow-along lyrics. In June and July 2027, the stage lights come on in Düsseldorf, Hamburg, Mannheim, Berlin, Hanover, Vienna and Munich.
A look inside the 6K area
This is what practising with cori looks like, in the app and in the browser.
All songs and appointments in one place
Children see exactly what they need: the season's official practice videos, warm-ups to get their voices going and their class's next rehearsal.
Official practice videos of the 2027 season
Warm-ups to get started
Class appointments with RSVP
Practise with video, chapter markers and follow-along lyrics
Every song has chapters like warm-up, choreo or the left and right part. Children jump straight to the part they want to practise with a single tap, and the lyrics follow along next to the video.
Chapter markers for warm-up, choreo, left and right
The follow-along lyrics highlight exactly the line that is playing
Sheet music as a PDF, just one tap away
Sing along with feedback
In cori's sing-along, children sing their part over the official playback. They see live whether they hit the notes, and the lyrics follow along line by line.
Left or right: every child practises their own part
Live feedback on the sung pitch
Lyrics follow along in sync with the music
New for the 2027 season
A lot has been added since the launch at the end of the 2026 season:
The 6K area in the browser
Practise without installing anything: on the school PC, the whiteboard or the laptop at home.
Classrooms for teachers
Create appointments, see RSVPs and organise your own group.
Follow-along lyrics and sheet music next to the video
Lyrics run in sync, and sheet music sits right next to the video as a PDF.
For teachers and choir directors
Less organisational work, more time for music
No more file chaos
No more sending YouTube links via WhatsApp. Everything is in the app, always up to date and always available.
A protected space
The 6K area is only accessible with an access code. GDPR-compliant, data hosted in Germany.
Your class at a glance
With the teacher key you create classrooms, plan appointments and see RSVPs. And for the children, everything stays free.
Anonymous, child-friendly, GDPR-compliant
In a project with over 100,000 children, data privacy is not a footnote. This is how cori protects your children's data:
Anonymous for children
No account of their own, no email address: children sign in with nothing but the access code and a freely chosen display name.
A child-friendly, closed space
No ads, no public profiles, no social features. Only those with an access code get into the 6K area.
The voice stays on the device
The sing-along analyses the voice right on the device. Children's recordings are never uploaded to our servers.
Hosted in Germany
All data is stored GDPR-compliantly on servers in Germany, with data minimisation as the default.
GDPR
compliant
🇩🇪 Servers in Germany
Ready in 3 steps
Get the app or open the browser
cori is free on the App Store and Google Play. Or practise right in the browser, no installation needed.
Enter your 6K code
Simply enter the access code you received from your choir director.
Practise & sing along
Sing along, listen anywhere and even get feedback!
Practical Answers
The 6K practice room is the official practice area for every child singing with 6K UNITED!. It holds all the songs of the 2027 season as practice videos with chapter markers, follow-along lyrics and sheet music, plus warm-ups to get voices going and your own group's appointments. It is there in the cori app and in the browser.
With the 6K access code you get from your teacher or choir director. In the app you enter it the first time you start it, in the browser at cori.music/6k-proberaum. Children need neither an email address nor a password for it, just the code and a first name.
Yes, since the 2027 season. On the school PC, at the whiteboard or on the laptop at home, you open the 6K practice room in the browser without installing anything, using the same access code as in the app. Songs, videos, follow-along lyrics, sheet music and the group's appointments are identical in both places.
Yes, completely. The 6K practice room in cori is free for all participating children. No subscription, no credit card, no hidden costs.
The cori app runs on iPhones and iPads (iOS 16 and up) and on Android devices (Android 8 and up), and it is free on the App Store and Google Play. On top of that, the 6K practice room works in the browser, with no installation at all.
cori is GDPR-compliant and hosts all data on servers in Germany. The 6K practice room is closed, with no public profiles and no social features. Children's audio recordings never leave the device and are not transferred to our servers. We consistently apply data minimisation and child-appropriate defaults.
The official practice videos with chapter markers (warm-up, choreo, left, right), sheet music and follow-along lyrics, warm-ups, a sing-along with live pitch feedback, groups with appointments for teachers and personal practice streaks.
6K UNITED! is the largest children's choir project in the German-speaking world. Every year, over 100,000 children learn a shared concert repertoire and perform it as a 6,000-voice choir in large arena concerts, in 2027 in seven cities across Germany and Austria. Find out more at 6k-united.de.
Write to us at info@getcori.app. We usually reply within one working day.
What else cori can do for your choir
Beyond 6K, cori is the perfect practice room for your choir. So you deliver at every concert.
Upload your own songs
Upload your own pieces or record them directly in cori. Not just for 6K, but for any repertoire.
Interactive exercises for every voice
cori generates individual exercises for soprano, alto, tenor and bass from every song. So every child practises exactly their part.
Rehearsal and event planning
Organise rehearsals, performances and events directly in the app. Your whole choir stays in the loop.