0x54ask

6 Downloads 16 Views v1.1 12.43 MB 4.1+

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(12.43 MB)

Editor's Overview

0x54ask is a calendar & agenda application developed by Tero Karvinen, packaged as a single Android APK of version 1.1 weighing in at 12.43 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 12.43 MB, so it installs quickly even on modest connections.
This build is signed by "Tero Karvinen" — 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

0x54ask is a todo.txt manager. It supports context (@W at work, @H at home...) and tags (+linux, +bank, +tero).

0x54ask forks SimpleTask Cloudless. It provides passive perks: data safety, automerge, filesystem protection - and it never connects Internet, at all.

Todo.txt manager: context and tags

Context: You write down a task. If it was the only thing, what would be the next action? Drill a hole for picture? If the wall is in your home, you've got to do it there. Thus, @H (at home).

Tags: I'll be working on +linuxeu project for the next 5 hours. Show me all tasks I can bill on that. Thus, filter by +linuxeu.

Plain text: Todo.txt is - surprise - plain text. You can edit it with vim, emacs, micro or nano. Todo.txt and calendar.txt use the same +plustags and @Contexts.

Fully offline, or synchronize how you like.

0x54ask passive perks

What does the 0x54ask fork bring to the table? Data safety, better sync, smaller attack surface, modern interfaces. These benefits work passively. You don't have to do anything to use them.

Keeps your data safe. It automatically detects if todo.txt has been modified by other programs (such as text editor or syncthing). Modifications appear as soon as 0x54ask sees them. Changes are stored as soon as they are made. Current state of file is checked again.

Automatic merge. If a conflict is detected, 0x54ask can often automatically merge the changes. This is possible, because todo.txt is a line based format, and many changes appear in different lines. Main approach to auto merge is generic and works, no matter which program made the changes. There is additional support for automatic resolution of Syncthing conflicts. Special support is needed, because these sync conflicts can happen while 0x54ask is not running.

Filesystem protection: You can pick the directory where todo.txt is. This will be the only directory available for the app. This restriction is enforced by the operating system. The whole filesystem backend was updated to use modern SAF, the Storage Access Framework.

No Internet, ever. There is no INTERNET permission, so the operating system prevents app from accessing the Internet. Any synchronization is handled by other applications of your choice, Syncthing (Syncthing fork) recommended. You can also use the app completely offline. Also, all networking related code was removed from the app.

0x54ask is Free, Open Source Software under GPL 3 license. I used new name and app id for 0x54ask, while also giving credit to upstreams of this fork. This way, upstream gets credit for their work, but not reports for my bugs.

Background

The original SimpleTask Cloudless aka simpletask-android was developed by Mark Janssen. The original is now archived and removed from F-Droid. The design and UI felt great, and I could not find an alternative that could compete.

0x54ask is a fork of willemw12/simpletask-android by Willem W, a fork of the original SimpleTask. Forking made sense, since some of the changes were large (SAF backend), some removed code (networking), and a key promise is not necessarily shared (no Internet access, and no plans to add it). Like original SimpleTask, willemw12 fork still asked for access to all files and photos on the phone. The fork had many improvements over the original, so it felt like a good starting point.

Artificial intelligence was used to help create the improvements after forking.

The task format is todo.txt by Gina Trapani. Todo.txt works well with calendar.txt.

Copyright 2026 Tero Karvinen TeroKarvinen.com, Mark Janssen, Willem W and other contributors.

Details

Version	v1.1
Size	12.43 MB
Developer	Tero Karvinen
Category	Calendar & Agenda
Package	com.terokarvinen.x54ask
Android	4.1+
Last Updated	Oct 30, 2026
Downloads	6

Frequently Asked Questions

Is 0x54ask 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 0x54ask require?
Android 4.1+ or newer. Installing on older devices may cause crashes or refuse to install.

Is 0x54ask safe to install?
We link to the exact APK published by Tero Karvinen. 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 0x54ask?
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 0x54ask

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 com.terokarvinen.x54ask.apk file from your Downloads folder.
Tap Install and wait for Android to finish.
Open «0x54ask» by Tero Karvinen 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.