Probability theory v8.5.4
APK · 21 MB · version code 805040 · Android 4.4+ · uploaded Jan 19, 2026
- Signature matches the Google Play version Details
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Answer this to unlock the download. It keeps automated downloaders away.
File information
- Version
- v8.5.4 (805040)
- Uploaded
- Jan 19, 2026
- Size
- 21 MB
- Requires
- Android 4.4+ (API 19)
- CPU support
- Any (no native code)
- Screen
- Small screens and larger
- MD5
- a357e931509edcd8beafe60a3a27c41c
- Signing certificate (SHA-1)
- 97:C0:90:78:45:8E:B0:1D:0D:1D:75:E5:0F:68:C1:E2:65:85:BF:D1
- Signed by
- CN=Kirill Sidorov, C=RU
- File name
- com-do-apps-catalog-286-805040-73203242-a357e931509edcd8beafe60a3a27c41c.apk
- Package
- com.do_apps.catalog_286
- Downloads (all versions)
- 50K+
- Age rating
- PEGI 3 · Everyone
What's new in v8.5.4
Some bugs fixed, performance improved
Permissions (10)
This version requests 10 permissions, 4 of them sensitive.
- Approximate location Sensitive android.permission.ACCESS_COARSE_LOCATION
- Modify shared storage Sensitive android.permission.WRITE_EXTERNAL_STORAGE
- Precise location Sensitive android.permission.ACCESS_FINE_LOCATION
- Read shared storage Sensitive android.permission.READ_EXTERNAL_STORAGE
- Full network access android.permission.INTERNET
- In-app purchases (Google Play Billing) com.android.vending.BILLING
- Prevent the device from sleeping android.permission.WAKE_LOCK
- Run at startup android.permission.RECEIVE_BOOT_COMPLETED
- View Wi-Fi connections android.permission.ACCESS_WIFI_STATE
- View network connections android.permission.ACCESS_NETWORK_STATE
Security & authenticity
Security rating: Trusted
Signing certificate
- Signature matches the Google Play version Checked by the source store on Jan 19, 2026.
- Certificate issued to “Kirill Sidorov” This is the certificate of the Google Play version.
Store checks
- Developer signature verified Jan 19, 2026
- Validated against Google Play Jan 19, 2026
- Uploaded by “appupdater” Gold tier · 117,810 followers · uploading since 2020
Scans come from the source store; the certificate comparisons are AAPKs's own, made from the files' published signatures. AAPKs doesn't scan files itself.
How to install Probability theory on Android 4.4+
You'll need about 42.1 MB of free space.
- Download the APK — tap Download APK above (21 MB). Chrome shows “File might be harmful” for every APK file; choose Download anyway only if you trust this file.
- Open the file — tap the download notification, or open Files › Downloads and tap com-do-apps-catalog-286-805040-73203242-a357e931509edcd8beafe60a3a27c41c.apk.
- Allow the install (first time only) — Android 8 and later asks for permission the first time an app opens an APK: tap Settings in the prompt, turn on Allow from this source, then go back. Manual path: Settings › Apps › Special app access › Install unknown apps (on Samsung: Settings › Apps › ⋮ › Special access). On Android 7 and older: Settings › Security › Unknown sources.
- Check the file (optional) — the MD5 of the downloaded file should be a357e931509edcd8beafe60a3a27c41c. If it differs, the file is damaged or was changed: delete it and download again.
- Tap Install — Android asks “Do you want to install this app?”. If Google Play Protect shows a warning, read it before you continue: the source store rated this file Trusted, but only install apps from sources you trust. If an earlier version is installed, this one only installs as an update when it is signed with the same certificate (SHA-1 shown above).
- Open Probability theory — tap Open on the install screen, or find it in your app drawer.
Common install problems
- “App not installed” — a version signed with a different certificate, or a newer version, is already installed (Android doesn't allow downgrades). Uninstall it first; back up your data, because uninstalling deletes it.
- “There was a problem parsing the package” — the file is incomplete, or your Android is too old (this version needs Android 4.4+). Download it again, or pick an older version.
- Blocked by Play Protect — Play Protect checks apps from outside the Play Store. Only continue if you trust the source.