CASSY App
v1.19 · 21.6 MB · code 1314
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File information
UpdatedFeb 3, 2026
PublishedOct 29, 2020
Packagede.ld_didactic.cassyapp
Versionv1.19 (1314)
Size21.6 MB
MD586748f12fe8ce0210fb61fd7fca2ec3b
Min SDK21
ABIsarmeabi-v7a, arm64-v8a
Malware scanTRUSTED
Signature SHA1FF:E8:95:11:C9:1A:1B:F8:B2:E0:41:2C:6B:9C:9D:56:42:3F:C9:6F
SignerCN=Michael Hund, OU=Unknown, O=LD DIDACTIC GmbH, L=Huerth, ST=Nordrhein-Westfalen, C=DE
Total downloads1,000
This version1,000
DeveloperLD DIDACTIC GmbH
Age ratingEveryone
What's new in v1.19
Saving and sharing experiments is now even easier.
The evaluations are easier to find via a new button.
Opening experiments now also works reliably under Android 12.
The evaluations are easier to find via a new button.
Opening experiments now also works reliably under Android 12.
Security scan
TRUSTED
- Developer signature verified 2026-02-03
- Signature SHA1 FF:E8:95:11:C9:1A:1B:F8:B2:E0:41:2C:6B:9C:9D:56:42:3F:C9:6F
- File MD5 86748f12fe8ce0210fb61fd7fca2ec3b
How to install CASSY App v1.19 on Android 5.0 Lollipop+
Takes about 2 minutes. You'll need roughly 21.6 MB of free storage.
- Grab de.ld_didactic.cassyapp_1314.apk — hit the Download button above (21.6 MB). If your browser warns about APK files, choose Keep or Download anyway — that warning fires on every APK, not just this one.
- Trust your browser to install — on Android 8+ go to Settings → Apps → Special access → Install unknown apps, pick the app you downloaded with (Chrome, Firefox, Files, etc.), and flip Allow from this source. On older Android, toggle Unknown sources under Security.
- (Optional) Verify the file — compute the MD5 of the downloaded APK and make sure it matches 86748f12fe8ce021…. Any difference means the file is corrupted or tampered — delete and re-download.
- Open the APK — tap the download notification, or find de.ld_didactic.cassyapp_1314.apk in your Files app under Downloads, then tap it. Android's package installer will appear.
- Check the signer — the install screen will name the publisher. For this build it should read CN=Michael Hund, OU=Unknown, O=LD DIDACTIC GmbH, L=Huerth, ST=Nordrhein-Westfalen, C=DE. If it doesn't match, cancel — you have the wrong file.
- Review permissions & tap Install — scroll the permission list, then confirm. If Play Protect flags it, tap Install anyway (this APK was scanned as TRUSTED).
- Done — open CASSY App — tap Open on the install screen, or find the CASSY App icon in your app drawer (this build targets armeabi-v7a/arm64-v8a devices).
Common install errors for CASSY App
- "App not installed" — usually means an older or differently-signed version is already on your device. Uninstall it first, then retry. Your data may be lost unless you back it up.
- "Parse error" — the APK is for a newer Android than yours. This version needs Android 5.0 Lollipop or later. Pick an older build from the versions list below.
- "There was a problem parsing the package" — the download was interrupted. Delete the file and re-download over Wi-Fi.
- Works on one phone but not another — this build ships armeabi-v7a/arm64-v8a native code. Devices with a different CPU will reject it.