Optimum: f. r. s.
v3.23.1 · 27.3 MB · code 994
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File information
UpdatedFeb 18, 2026
PublishedSep 27, 2021
Packagecom.optimum3.client
Versionv3.23.1 (994)
Size27.3 MB
MD5fb7802e9170bce810f5b6179135e3ca7
Min SDK24
ABIsx86, x86-64, armeabi-v7a, arm64-v8a
Malware scanTRUSTED
Signature SHA17A:DD:27:71:3A:06:C8:E6:93:38:61:F6:8A:30:DB:C2:2F:07:D5:D6
SignerCN=Android, OU=Android, O=Google Inc., L=Mountain View, ST=California, C=US
Total downloads50,000
This version50,000
DeveloperOPTIMUM: field reporting system
Age ratingEveryone
Security scan
TRUSTED
- Developer signature verified 2026-02-18
- Signature SHA1 7A:DD:27:71:3A:06:C8:E6:93:38:61:F6:8A:30:DB:C2:2F:07:D5:D6
- File MD5 fb7802e9170bce810f5b6179135e3ca7
How to install Optimum: f. r. s. v3.23.1 on Android 7.0 Nougat+
Takes about 2 minutes. You'll need roughly 27.3 MB of free storage.
- Grab com.optimum3.client_994.apk — hit the Download button above (27.3 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 fb7802e9170bce81…. Any difference means the file is corrupted or tampered — delete and re-download.
- Open the APK — tap the download notification, or find com.optimum3.client_994.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=Android, OU=Android, O=Google Inc., L=Mountain View, ST=California, C=US. 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 Optimum: f. r. s. — tap Open on the install screen, or find the Optimum: f. r. s. icon in your app drawer (this build targets x86/x86-64/armeabi-v7a/arm64-v8a devices).
Common install errors for Optimum: f. r. s.
- "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 7.0 Nougat 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 x86/x86-64/armeabi-v7a/arm64-v8a native code. Devices with a different CPU will reject it.