App Lock v1.4.1
APK · 4.6 MB · version code 15 · Android 4.1+ · uploaded May 16, 2021
- Same certificate as the other version checked Details
Quick check before downloading
Answer this to unlock the download. It keeps automated downloaders away.
Compared with the latest version
The latest version is v1.4.2, uploaded Sep 18, 2025 — about 4 years after this one.
- Size: this file is 4.6 MB; the latest is 4.5 MB (55.4 KB smaller).
- Both versions request the same permissions.
File information
- Version
- v1.4.1 (15)
- Uploaded
- May 16, 2021
- Size
- 4.6 MB
- Requires
- Android 4.1+ (API 16)
- CPU support
- Any (no native code)
- Screen
- Small screens and larger
- MD5
- 176557b450710cf11ebb6517d3375755
- Signing certificate (SHA-1)
- DF:9B:C0:4F:7E:D6:CB:23:E9:CB:3B:39:15:6D:76:1D:B2:6B:27:F5
- Signed by
- C=TH
- File name
- nu-app-lock-15-58098597-176557b450710cf11ebb6517d3375755.apk
- Package
- nu.app.lock
- Downloads (all versions)
- 100K+
- Age rating
- PEGI 3 · Everyone
What's new in v1.4.1
- Add option to make pattern invisible while drawing pattern.
- Fix bug : cannot disable fingerprint.
- Performance and stability improvements.
Permissions (10)
This version requests 10 permissions, 1 of them sensitive.
- Package usage stats Sensitive android.permission.PACKAGE_USAGE_STATS
- Full network access android.permission.INTERNET
- Get tasks android.permission.GET_TASKS
- Google Play install referrer com.google.android.finsky.permission.BIND_GET_INSTALL_REFERRER_SERVICE
- Prevent the device from sleeping android.permission.WAKE_LOCK
- Reorder tasks android.permission.REORDER_TASKS
- Run at startup android.permission.RECEIVE_BOOT_COMPLETED
- Run foreground services android.permission.FOREGROUND_SERVICE
- Use fingerprint hardware android.permission.USE_FINGERPRINT
- View network connections android.permission.ACCESS_NETWORK_STATE
Security & authenticity
Security rating: Trusted
Signing certificate
- Same certificate as the other version checked
Store checks
- Developer signature verified May 16, 2021
- Uploaded by “catappult” Platinum tier · 1,377 followers · uploading since 2018
Scans come from the source store; the certificate comparisons are AAPKs's own, made from the files' published signatures (1 other version compared). AAPKs doesn't scan files itself.
How to install App Lock on Android 4.1+
You'll need about 9.2 MB of free space.
- Download the APK — tap Download APK above (4.6 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 nu-app-lock-15-58098597-176557b450710cf11ebb6517d3375755.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 176557b450710cf11ebb6517d3375755. 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 App Lock — 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 4.1+). 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.