Crystal Ball

8 Downloads 11 Views v0.3 12.11 MB 4.1+

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(12.11 MB)

Editor's Overview

Crystal Ball is a multimedia application developed by Kreuder, packaged as a single Android APK of version 0.3 weighing in at 12.11 MB. The package targets Android 4.1+ and above. Below you'll find the publisher's own description, a quick spec sheet, and a short buyer-beware checklist so you know exactly what you're installing before tapping download.

Install Checklist

Only download through the button on this page — never from third-party mirrors or shortened links, which are the most common way malware spreads.
File size is a light 12.11 MB, so it installs quickly even on modest connections.
This build is signed by "Kreuder" — always verify the developer name matches what's listed on the app's official store page before installing an update.
After install, Android may prompt you to allow "Install from unknown sources" — approve only this one install, then revoke the permission in Settings > Apps > Special access.
We link directly to the APK file or the publisher's repository; we do not modify the binary. Always run a virus scan after any sideloaded install.

About this app

Crystal Ball listens to your guitar and tells you what chord you just played. Press Detect single chord, strum, and it names the chord and draws how to fret it — with the chords it nearly picked instead one tap away, and other ways to play the same one further up the neck. Capture a whole part and it becomes a song sheet you can keep, correct and share.

Early-stage release — expect rough edges. Feedback and bug reports welcome via Issues.

Features:

* Detect a chord by ear — press, strum, done. It listens until the answer settles rather than for a fixed time, so a clean open chord resolves in about a third of a second; strumming again restarts it, so a bad take needs no second press.
* Ranked alternatives — the best fit is a guess, not ground truth, so the runner-ups sit under it and one tap swaps the page over to any of them.
* Chord shapes, not just names — the most idiomatic grip drawn large, plus other voicings walking up the neck. Open shapes are the ones a player expects to see, by name.
* Capo-aware — detection is unaffected (the microphone hears the real chord either way), but the shapes are redrawn behind the capo, fret numbers stay as printed on your neck, and anything the capo pushes off the end is dropped rather than offered. Chords can be named by what you hear or by the shape your hands make.
* Song sheets — capture a part chord by chord, name it Intro or Chorus, reorder the parts, and read the whole song back as diagrams. Parts can be renamed, chords fixed by hand without playing them again, and the finished sheet shared to any app.
* Chord dictionary — look any of 240 chords up by hand, without playing a note. Sixths, ninths, 6/9 and 13ths included.
* English and German — pick the app's language without changing the whole phone. German note names (H/B) are a separate switch, since being taught H is not the same as reading German.
* Session comforts — System/Light/Dark themes, keep-screen-on, an optional capo prompt at launch, an in-app quick help sheet, and backup/restore for your songs. Preferences persist across launches.

Heard: maj, min, 7, maj7, m7, sus2, sus4, across all 12 roots. Drawn: those plus dim, aug, m7b5, dim7, 7sus4, 6, m6, add9, 9, maj9, m9, 6/9 and 13 — yours to look up and write down, though the microphone will not name them. Shapes assume standard tuning (EADGBE).

Honest about accuracy: template matching on clean triads is good, and degrades on a boomy room, a badly tuned guitar, or a phone held across the room. It is a practice aid, not ground truth — hence the runner-up row, which is one tap from correcting it.

Microphone access is required — listening to your guitar is the whole app. Audio is analysed on the fly and never recorded, stored or sent anywhere; the app has no network permission at all.

No ads, no trackers, no network access.

Details

Version	v0.3
Size	12.11 MB
Developer	Kreuder
Category	Multimedia
Package	de.singular.crystalball
Android	4.1+
Last Updated	Oct 29, 2026
Downloads	8

Frequently Asked Questions

Is Crystal Ball free to download?
Yes. The APK file linked from this page is free. The developer may offer in-app purchases once installed, but obtaining the installer itself costs nothing.

What Android version does Crystal Ball require?
Android 4.1+ or newer. Installing on older devices may cause crashes or refuse to install.

Is Crystal Ball safe to install?
We link to the exact APK published by Kreuder. We do not modify the file. Still, as with any sideloaded app, scan it with a reputable antivirus before opening it, and only grant permissions the app genuinely needs.

How do I update Crystal Ball?
Install the newer version on top of the old one — Android will keep your data. If the signature differs, uninstall first (you may lose local progress).

Why is the app not installing?
Common causes: not enough storage, an older Android version than 4.1+, or a conflicting build already installed. Free up space, check your OS version, and uninstall any previous copy before retrying.

How to Download & Install Crystal Ball

Tap the Download APK button above and save the file to your device.
Open your device Settings → Security (or Apps → Special access → Install unknown apps) and allow your file manager or browser to install unknown apps for this one file only.
Open the downloaded de.singular.crystalball.apk file from your Downloads folder.
Tap Install and wait for Android to finish.
Open «Crystal Ball» by Kreuder and grant only the permissions it actually needs.
Revoke the "unknown sources" permission once you are done installing.

Note: this page hosts or links to the installer only. The application name, icon and description are provided for identification. All trademarks belong to their respective owners.