Editor's Overview
BayesianBahn is a public transport application developed by DerWeh, packaged as a single Android APK of version 0.2 weighing in at 5 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 5 MB, so it installs quickly even on modest connections.
- This build is signed by "DerWeh" — 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
times and connections with DB's official apps.
BayesianBahn predicts when you will actually arrive — as a full
probability distribution, not a single number.
Enter where you start, where you want to go and when (also future trips):
the app searches direct trains and journeys with one change — routes
needing two or more changes are not covered yet, so it will sometimes
find fewer connections than DB's own apps. For each option it shows:
* the median predicted arrival time at your destination,
* an 80% credible interval,
* the full delay distribution as a chart,
* the probability of catching each connecting train,
* a Deutschland-Ticket filter that keeps you on regional trains.
Transfers are propagated with Bayes' theorem: you board the first
connecting train that has not left yet — so a delayed earlier train
counts as catchable, and a missed connection honestly shifts the whole
distribution. Live station boards and per-train predictions (including
cancellation rates) are also available.
Predictions are empirical: they come from months of real historical runs
of that exact train at that station (collected from Deutsche Bahn's
public IRIS API, CC BY 4.0), reweighted for recency and weekday. When
DB reports an actual delay the forecast is anchored on it; when it
reports nothing — which it does for most trains until shortly before
departure — the history is left to speak for itself, which measurably
beats treating the timetable as a forecast. Delay history updates
in-app — a small daily data release keeps predictions fresh to within a
day. Trains without history get an honest Bayesian prior estimate.
The app talks only to the keyless public IRIS timetable endpoint and the
project's own data releases, needs no account, no API key, no Google
services, and collects no data.
Details
| Version | v0.2 |
|---|---|
| Size | 5 MB |
| Developer | DerWeh |
| Category | Public Transport |
| Package | io.github.derweh.bayesianbahn |
| Android | 4.1+ |
| Last Updated | Oct 28, 2026 |
| Downloads | 9 |
Frequently Asked Questions
Is BayesianBahn 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 BayesianBahn require?
Android 4.1+ or newer. Installing on older devices may cause crashes or refuse to install.
Is BayesianBahn safe to install?
We link to the exact APK published by DerWeh. 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 BayesianBahn?
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 BayesianBahn
- 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
io.github.derweh.bayesianbahn.apkfile from your Downloads folder. - Tap Install and wait for Android to finish.
- Open «BayesianBahn» by DerWeh 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.
