A simple Android app that helps you improve your working memory
About this app
Eidetic is an app for improving and testing your working memory. All you need to do is press the buttons in the right order. It's harder than it looks.
Background
The chimp test, also known as the Ayumu memory test, is a test designed to assess working memory.
It was popularized by a study conducted at the Primate Research Institute of Kyoto University in Japan, where chimpanzees demonstrated remarkable short-term memory abilities.
Chimps seem to, effectively, have a photographic memory (eidetic memory).
Untrained humans generally perform significantly worse than chimpanzees on the chimp test. So, this app trains you. The hope is that we can eventually match or beat chimp records.
Gameplay • Numbers from 1 to 9 are displayed randomly
• You must memorize the positions of the numbers
• Once you press 1, all buttons display a ?
• You need to then use your memory to press 2, 3,..., 9
• It's game over if you press the wrong button thrice.
Licensed under Apache-2.0.
What's New in v1.4.4
Imported from the F-Droid repository index.
- - Bug fixes, improved gameplay
Version history
May 2, 2025 · 4.7 MB · Android API 26–35 · code 12
Imported from the F-Droid repository index.
- - Bug fixes, improved gameplay
SHA-256 3e499242bc63bc9151b24f98585a0db828acab10b0abbfdebda71b6164f8918f
Apr 25, 2025 · 4.7 MB · Android API 26–35 · code 11
Imported from the F-Droid repository index.
- - Heart regeneration. You now regain a lost heart every time you complete 5 attempts successfully.
- - There's now a maximum time limit of 1 minute.
SHA-256 f253f0674eb8ee8f1250bc547f3c9ef1d25631d8ffec9406747483db2cc80f81
Apr 5, 2025 · 4.7 MB · Android API 26–35 · code 10
Imported from the F-Droid repository index.
- - Added support for more numeral systems
SHA-256 f24eed5097a0fb3bc507bd4d282307600bbddb3bb4491cb428fa73c2f6eca634
Will it run on your device?
78%
- Runs on a broad range of modern Android versions.
- ABI coverage is focused on newer 64-bit devices.
- Aligned with the latest Android target SDK expectations.
Installation Guide
Open Settings on your Android device
Go to Security → Unknown sources (or Install unknown apps)
Enable "Allow from this source" for your browser or file manager
Open the downloaded APK file from your Downloads folder
Tap "Install" and wait for installation to complete
Launch the app from your home screen
Make sure to re-enable Unknown Sources restrictions after installation for security.
How to install this safely
How to verify the file you downloaded
Before you install anything, confirm the file is the one described here. On a computer, run shasum -a 256 your-download.apk (macOS or Linux) or certutil -hashfile your-download.apk SHA256 (Windows), then compare the output character-for-character with the SHA-256 on this page. If a single character differs, the file is not the build we recorded — delete it.
What the signing certificate proves
Every Android app is signed with a private key that only its developer holds. The fingerprint on this page is a hash of the matching public certificate, and it proves continuity rather than identity: it tells you a build came from whoever signed the earlier ones. Android enforces this at install time — if a package claiming to be io.github.hathibelagal.eidetic is signed with a different key, the system will refuse to install it over your existing copy. A fingerprint that changes between releases is worth pausing on, because a repackaged app that has been modified by someone else cannot keep the original signature.
How to roll back to an earlier version
If the current release misbehaves, 1.4.3 is the last build before it. Android will not install an older version code over a newer one, so you must uninstall Eidetic first — which clears its local data unless you have a backup. Reinstall the older APK only if its signing fingerprint matches the build you already trust, and check the API range: an older release may target an Android version your device has moved past.
Why we list sources instead of hosting everything
The official store channel is almost always the right choice: it updates automatically and carries the publisher's own distribution guarantees. A direct APK is useful when a device has no store access, when a rollout has not reached your region, or when you need a specific version — and only when the publisher has authorized that copy. APKBrowse does not list pirated, cracked, or unauthorized rebuilds of Eidetic, and a listing is removed when the evidence for it stops holding up.
Get Eidetic
Every source we list for io.github.hathibelagal.eidetic is legality-reviewed. Pirated or cracked builds are never offered.
Other sources
F-Droid listing
officialF-Droid builds this app from source and signs it. This is its official listing, with older builds and full release notes.
Source code
verified publisherThe upstream repository this build is compiled from.
We check legality and signature continuity, but device behaviour still varies. Install at your own discretion.
App Information
Security Verification
We record provenance; we do not run malware scans. Verify the hash yourself before installing.
SHA-256 Hash
3e499242bc63bc9151b24f98585a0db828acab10b0abbfdebda71b6164f8918f
Signing certificate
f0025114ee3c2640b1316a481744e2ef2dfc9e92eb15dc6f4599915d9fe3b6b2
Permissions Required
Previous Versions
The signing certificate fingerprint for this release is on record, so a build that does not match it did not come from this publisher.
Report a problem with this listing
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