Calendar

284 open source Calendar apps

LifeDots - Diary in 8 dimensions
APK
LifeDots is for recording and analysing your life with ease in the 8 dimensions of time, event, location, notes and photo. Currently you can record any event by touching on an icon that you create, entering notes and attaching photos. Locations are automatically recorded (after you activate) in the background. Then you can browse your history, analyze statistics in charts, check the timeline of any event, and see your past geo locations. Further more, for easier viewing life from various perspectives, these analytic functionalities are interconnected: check timeline on any pieve of a piechart, review related history about a dot on the timeline, look at geographical passages related to a period of history, and go back to related history on a dot on the map. LifeDots is a free and open-source software. There is no advertising and no requirement for purchase of kind. All of your data remain on your own device. Internet connection is only needed for dynamically downloading the necessary and free map tiles when you need.
F-DroidGitHub
LightPlan - Reminder & Planner
APK
Light Planner is a FOSS, simple, and intuitive app that will help you with planning events, tasks, or achievements you want to reach! ============== How does it work? ============== • Add your tasks in a chosen year quarter • Write up a title and a description and pick a deadline for it That’s it! Upon entering the task area, you will be shown the time you have left to complete it and (optionally) the subtasks you have created in it. ============== Who is it made for? ============== Anyone! No matter the age or height, you can use the app to plan ahead and keep track of the time you have left to complete it at any time. ============== How is it different from other apps? ============== This app was designed to be simple and intuitive, while still looking slick and unintrusive. We also don’t collect any data from users (everything is stored on your device), which means you don’t have to create/link an account and you won’t have to deal with any pesky ads! Additionally, the project is open-source, so if you feel like changing or adding features, you can do it! (link to the project repository: https://github.com/XDDK/LightPlan). I hope you'll find this app useful!
F-DroidGitHub
LinCal
APK
"LinCal" is short for "Link Calendar" and allows to show links or small messages at predefined points in time, in the form of notifications. If the message is a link, it can be opened by clicking the notification. Calendars are created as a text file using a simple format and can then be loaded into the app. Use it as Advent calendar or just to make someone happy!
F-DroidGitHub
Linwood Flow Nightly
APK
Linwood Flow is a free, opensource time and event management software. You can choose where your data is stored and who can access it. Group your events and manage places and people. The app is available for Windows, Linux, Android and Web. * Simple and intuitive: Every tool is in the right place. Open the app and start managing your time. Invite people to your events and share your calendar with them. * Support your favorite formats: Import and export your old notes and events. Set the app as your default calendar app and use it with your favorite apps. * Works on every device: The app is available for android, windows, linux, and in the web. You can use it on your phone, tablet, or computer. * Choose where your data is stored: You can choose to store your data locally, in your favorite cloud (caldav) or decentralized using S5. You can also export your data to a file and import it again. * Available in many languages: The app is available in many languages. Help us to translate this app to your language. * FOSS: The app is open source and free. You can contribute to the project and help to make it better. * Use it offline: You can use the app offline. You can draw, paint, and export your notes without an internet connection. * Manage your time: You can manage your time using a calendar. You can add events to it and share them with your friends. * Manage your places: You can add places to the app and share them with your friends. Keep track which places are free and which are busy. * Manage users: Add users to the app to keep track of who is available and who is not. You can also share your calendar with them. Add birthdays to the app and get a notification when it is time to celebrate. * Manage your tasks: You can add tasks to the app and share them with your friends. You can also add your favorite tasks to the app. Set a deadline and get notified when it is due. * Take notes: You can add files and notes to your events. Add a backlog to your events to keep track of your progress. * Group your events: Group your events to know which events are related to each other. You can also add tags to your events to find them faster. * Irregular events: You can add irregular events to the app. Have irregular meetings? Add them to the app and get notified when it is time to meet. Simply copy the event and change the date.
F-DroidGitHub
Lux Alarm
APK
Stop Oversleeping with Lux Alarm Tired of hitting snooze and waking up late? Lux Alarm ensures you actually get out of bed by requiring light to silence the alarm. How it works To stop the alarm, you must get up and open your blinds or turn on the light. The app uses your phone's sensor to detect brightness; by the time the alarm turns off, you are already on your feet and ready to start your day. Key Features • Smart Light Detection: Uses your phone's sensor to ensure the alarm only deactivates once your environment is bright. • Adjustable Sensitivity: Customize the required light level to account for gloomy weather or different room setups. • Modern Interface: A clean, intuitive design based on Material Design 3 for easy navigation. • Circadian Support: Waking up with light helps regulate your natural sleep cycle and reduces morning grogginess.
F-DroidGitHub
M
MRMCD 2025 Schedule
APK
Programm zur 📂 MRMCD 📂 Konferenz 🔍 https://2025.mrmcd.net Funktionen * Tagesüberblick über alle Programmpunkte * Beschreibung von Veranstaltungen lesen * Veranstaltungen in persönlicher Favoritenliste verwalten * Alle Veranstaltungen durchsuchen * Favoritenliste exportieren * Alarm für Veranstaltungen setzen * Veranstaltungen in Kalender eintragen * Link zu Veranstaltungen mit anderen teilen * Programmänderungen einsehen * Veranstaltungen bewerten * Integration mit dem Engelsystem-Projekt https://engel.mrmcd.net - Online-Tool für Helfer- und Schichtplanung auf großen Events * Integration mit Chaosflix https://github.com/NiciDieNase/chaosflix - Android App für https://media.ccc.de, teile Fahrplan-Favoriten mit Chaosflix und importiere sie als Bookmarks (RIP NiciDieNase) 🔤 Unterstützte Sprachen (Programmtexte ausgenommen) * Dänisch * Deutsch * Englisch * Finnisch * Französisch * Italienisch * Japanisch * Litauisch * Niederländisch * Polnisch * Portugiesisch, Brasilien * Portugiesisch, Portugal * Russisch * Spanisch * Schwedisch * Türkisch 💡 Inhaltliche Fragen zum Programm kann nur das MRMCD-Team beantworten. Diese App stellt lediglich die Programmpunkte zur Verfügung. 💣 Fehlerberichte sind herzlich willkommen, aber achte darauf, dass du erklärst, wie man den Fehler reproduzieren kann. Der Issue-Tracker findet sich hier: https://github.com/EventFahrplan/EventFahrplan/issues 🏆 Die App basiert auf der EventFahrplan-App https://f-droid.org/packages/info.metadude.android.congress.schedule/ für den Kongress des Chaos Computer Clubs. Der Quellcode der Anwendung ist auf GitHub https://github.com/johnjohndoe/CampFahrplan/tree/mrmcd-2025 zu finden. 🎨 MRMCD-Design von Leif Niemczik, https://leifs.website
F-DroidGitHub
Material Tea Timer
APK
Material design themed tea timer. Time your tea with material style. Shows you temperature and time quickly. Have a great tea!
F-DroidGitHub
Meditation
APK
This is a meditation timer. Minimalistic, reliable, and truly elegant. Features * Simple, elegant, and intuitive * No distractions - only the essential features * Beautiful assortment of bell and gong sounds * Custom volume adjustment of the bell sounds * Reliable countdown timer * Pre-meditation delay * Intermediate meditation intervals * Free and open-source software Description Meditation is a truly minimalistic countdown timer for meditation, with a clean user interface and no clutter. The minimalism of the app embodies meditation's actual purpose. A notable feature of the app is the ability to customize the volume of the notification bells independently of system volume. This allows you to set a predefined volume so that the sounds will reliably play at the same loudness every time. No more mid-meditation worrying that you remembered to turn the volume up! Another important feature is for the timer to be as reliable as possible, to ensure an accurate meditation time and prompt ending sound notification. This is achieved by starting a foreground service and disabling battery optimization. Reliability is of extreme importance to a meditation tool in order to eliminate all possible worries about the timer not behaving correctly. Just press the button and start!
F-DroidGitHub
Meditation Assistant
APK
This application assists with both timed (via duration or ending at a specific time) and untimed sessions, with numerous customizations, including start/interval/end sounds and device behavior. It also provides a monthly overview of your progress. A major feature in this application is the ability to share your sessions online. Though entirely optional, sharing your progress online adds another dimension to your accountability. Now that you've gone public, as your meditation streak increases more users will see it as a goal of their own. One user has posted over 500 days of consecutive days of meditation. Your meditation streak is the number of consecutive days you have recorded at least one session. As your streak grows, "not breaking the chain" becomes quite important. Soon you will be meditating once a day, even if it's five or ten minutes out of your schedule.
F-Droid
Meditation Timer
APK
Meditation Timer for Android is a free, open source app that can count and beep. It helps with repeating tasks, such as meditation. In essence, it is a simpler version of Foto Timer, and a rewrite of the original Meditation Timer for PalmOS from 20 years ago. Meditation Timer is working with "processes", which define how Meditation Timer counts, and how often it beeps. Processes can also be "chained" together, meaning that a process can automatically lauch another. Meditation Timer contains absolutely no AI whatsoever.
F-Droid
MeeRoo
APK
MeeRoo is an Android app to manage reservations for meeting rooms.Main purpose of this app is to display the availability of an meeting room. It is expected to have one tablet or phone next to the meeting room to see if it is available, see the current and upcoming meetings and reserve the room now or in the future. There is an overview for all meeting rooms, too. This makes it easy to find available rooms or a current meeting very quickly.How it worksThe app reads calendar and event data stored on the device. To get this to work the calendars must be configured in the android calendar on the device. On the first start of the app you have to choose the calendar mode (for synchronization). This is necessary, because Google Calendar marks meeting rooms as resources. With CalDav synchronised calendars are storing every calendar as normal calendars, no difference between a personal calendar and a meeting room (resource).Supported calendar synchronizationsGoogle CalendarCalDav Calendar
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Meeting Cost Clock
APK
Clock, which measures the time in a currency value (EURO or Dollar). It can show, how expensive a meeting will be taking into account the number of participants and a mean value of a price per person per hour.
F-Droid
Metric Time
APK
This app provides a widget for your home screen that shows the current time in Metric Time (Decimal Time). You can read more about this time format here https://en.wikipedia.org/wiki/Decimal_time.
F-DroidGitHub
Micro Timer
APK
Micro Timer is a tiny, microwave-inspired timer app for Android. Instead of inventing yet another clever, pretty, tedious method of inputing time, Micro Timer uses the tried-and-true 10-key pad commonly found on microwave ovens.
F-DroidGitHubIzzyOnDroid
Min Time
APK
Min Time is a countdown app. It's main goal is to help you structure your talks and presentations. It divides the talk time into three phases: green, yellow and red. With a glimpse you get an idea how much time is left. For example, a 70 minutes talk could be divided into 50, 15 and 5 minute segments. Once started, Min Time counts down from 70 to 0, changing colors and vibrating when a new phase is reached. During presentation you can switch to other apps. The app is intentionally kept simple. Just a few taps and you are ready to give your talk. To finish your presentations and tasks just in time.
F-Droid
MinCal Widget
APK
A Minimal Calendar Widget that's always on current date's month. Features: * Contains no ads or payments * Always on current date’s month * 3x2 (resizable) * Displays all events from your calendars with a symbol set (high number becomes generic) * Native widget configuration access or press widget’s top right corner * Pressing on any other part of the widget opens calendar application * Configurable: start day of the week, calendar (gregorian or holocene), show declined events, focus on current week, open calendar on clicked day, theme, symbol set, symbol set colour, transparency, text size
F-DroidGitHubIzzyOnDroid
Mindwtr
APK
Mindwtr is a complete Getting Things Done (GTD) productivity system designed for "Mind Like Water."Built for speed and privacy, it gives you a powerful, distraction-free way to capture and organize your life without cloud subscriptions.DESIGNED FOR FOCUSMindwtr is simple by default and powerful when you need it.Whether you are capturing a quick thought on the go or planning a complex project, the interface gets out of your way.CORE GTD WORKFLOWCapture: Instantly add tasks to your Inbox the moment you think of them.Clarify: Process your inbox quickly with the 2-minute rule.Organize: Sort tasks into Projects, Contexts (@work, @home), and Areas.Reflect: Stay on top of your goals with the built-in Weekly Review.Engage: Filter Next Actions by context or energy level to know exactly what to do next.POWERFUL FEATURESFocus View: A unified dashboard combining your Agenda and Next Actions.Kanban Boards: Visualize your projects with drag-and-drop boards.Local-First: Your data lives on your device. No login required, no tracking.Markdown Support: Add rich notes and descriptions to your tasks.Flexible Sync: Seamlessly sync with your desktop via File Sync (iCloud Drive, Syncthing) or WebDAV (Nextcloud).PRIVACY FOCUSEDWe believe your tasks are your private business. Mindwtr works completely offline and does not track your data or require an account.
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Mindwtr - GTD Task Manager
APK
Mindwtr (pronounced "mind water") is a free, open-source task manager and to-do list built for Getting Things Done (GTD). It is local-first and privacy-first by default. No account required. No cloud dependency. Your data stays on your device unless you choose to sync, export, or back it up. Use Mindwtr as an offline task list for your whole life: capture inbox items, clarify next actions, organize projects, and review what matters without giving a company your personal task data. KEY FEATURES: - GTD task manager: Inbox, Next, Waiting, Someday, Projects, Areas, and Contexts map directly to the Getting Things Done workflow. - To-do list and offline task list: Works without an internet connection, with fast local storage on your device. - Kanban board: Visualize work with board view and drag-and-drop task flow. - Projects and Areas: Keep complex goals organized without turning every task into a calendar event. - Review workflow: Daily and weekly review tools help you keep commitments current. - Optional sync and backup: You decide if and where data syncs. - Open source: Transparent code, no account lock-in, and no subscription required. PRIVACY BY DESIGN: - No account required. - No cloud dependency. - Your data stays on your device. - Mindwtr does not sell your task data. Whether you are a GTD veteran, building a private to-do list, or looking for an offline task manager with kanban board support, Mindwtr helps you reach mind like water.
F-DroidGitHubIzzyOnDroid
Minidoro
APK
Minidoro is a very minimalist but reliable Pomodoro® timer, following Pomodoro® Technique very rigorously. Pomodoro® Technique is extremely simple but efficient time management technique developed by Francesco Cirillo. The proposal is it's easier to concentrate on work for a relatively short period (i.e., 25 min) keeping in mind you can take a rest or switch to another activity after that. That's very simple: You split your work for 25 minute intervals, separated by short break periods In these 25 minute intervals try to focus on your work as much as possible, try to not distract yourself and to avoid other distractions After a 25 minute interval take a 5 minute break. During this break do any other activities except for the previous work Return to the work after the break (or not, if you've finished) Take a long break about 10–30 minutes after every 4 work intervals Full Pomodoro® Technique description on the author's website The Minidoro app may help you in Pomodoro® Technique adoption! Minidoro has: Minimalist user interface: only countdown screen with big digits, it's on all the time while timer's on See only how much time left, no other distractions It may turn Do-not-Disturb Mode in your device, no other apps will distract you You may count your distractions, by yourself or by outside You may set up your preferences: periods duration, long break frequency, notifications Dark theme (the only) No ads Works on any Android device, phone, table or watch, you may utilize even your old smartphone Proper work on Samsung® phones and tables (https://DontKillMyApp.com is not applicable) Wear OS notice It would be a great feature that Minidoro running on Wear OS turns DnD mode on both Wear OS and Android device. It should be generally possible since Wear OS may turn DnD on Android devices. But there's one nuisance. It's not possible to allow any app to operate DnD Mode in Wear OS from Wear OS UI. The only way to allow Minidoro to operate DnD in Wear OS is ADB command (no root should be needed). Install Minidoro, turn Wear OS in debug mode and connect to computer. After that for Wear OS 2.2 (based on Android 9) and above run this: "adb shell cmd notification allow_listener com.github.ympavlov.minidoro/com.github.ympavlov.minidoro.dnd.DndModeServiceV21" For any other Wear OS version below (based on Android 8.1 and below) use this: "adb shell settings put secure enabled_notification_listeners com.google.android.wearable.app/com.google.android.clockwork.stream.NotificationCollectorService:com.github.ympavlov.minidoro/com.github.ympavlov.minidoro.dnd.DndModeServiceV21" Pomodoro® is a registered trademark Francesco Cirillo. This app is not affiliated with Francesco Cirillo.
F-DroidGitHub
Month Calendar Widget
APK
A Month Calendar widget for Android 4.1+ Month Calendar Widget is a simplistic, cute widget that delivers you a quick overview of the respective month and was written in a way to respect your privacy.
F-DroidGitHub
Moon Phase
APK
Shows the real time view of the Moon, providing information about the current moon phase. This code has been originally belonged to the set of "shallow sky" astronomy applets, developed by Akkana Peck as long ago as in 1996 to run on Sharp Zaurus PDA.
F-DroidGitHub
MorphClock
APK
A simple and beautiful bedside clock. Features: * One time morphs into the next as time ticks by. * Background changes to match the sun's position where you live. * Large, easy-to-read time, appropriate to any device. * Subtile animations don't distract from work or sleep.
F-DroidGitHub
My Banq
APK
Connect to BAnQ (Bibliothèque et Archives nationales du Québec), the Library and National Archive of Québec, and keep track of the borrowed items linked to your subscription. Features include: * List your borrowed items * Receive notifications when the return date is approaching * Renew your borrowed items * Add several BAnQ accounts
F-Droid
NFC Alarm Clock
APK
Customize how your alarms look, easily create/delete alarms, and more. Each alarm can be configured however you want to use it. For those that struggle to wake up, you can restrict the volume or have it gradually increase when your alarm goes off. You can also use an NFC card or tag to dismiss your alarm. See the full list of features below for a more detailed look into all the things you can do. Features: * Edit and view alarms all in one screen. * Swipe left to delete an alarm. * Swipe right to copy an alarm. * Play music from your phone to wake up. Can even choose to play all the music in a folder. * Use NFC to dismiss an alarm. This is optional and can be set on a per-alarm basis. Found by selecting the gear icon next to the volume slider of an alarm. * Gradually increase the volume when your alarm goes off. This is optional and can be set on a per-alarm basis. Found by selecting the gear icon next to the volume slider of an alarm. * Restrict changing the volume when your alarm goes off. This is optional and can be set on a per-alarm basis. Found by selecting the gear icon next to the volume slider of an alarm. * Text-to-speech when your alarm goes off. It will say the current time to you at whatever cadence you choose. This is optional and can be set on a per-alarm basis. Found by selecting the gear icon next to the volume slider of an alarm. * Choose which audio source you want the alarm sound to play out of (Alarm, Call, Music, Notification, Ringtone). This is optional and can be set on a per-alarm basis. Found by selecting the gear icon next to the volume slider of an alarm. * Customize the colors of: the theme, name of the alarm, days in which the alarm runs, time, and AM/PM. Found in Settings › Appearance. * View statistics of how many alarms you have dismissed/snoozed/missed, and how many you have created/deleted. Permissions: * NFC: (Optional) Allow the app to detect NFC tags. * Storage: (Optional) Read music that is stored on the phone. You are prompted to enable this permission if and only if you choose to play music as the alarm ringtone. Otherwise, this permission is unused. * Vibrate: (Optional) Allow the app to vibrate the phone. * Startup: (Required) Restore alarms when the phone is turned on. By default, Android will delete alarms when the phone is turned off. * Wakelock: (Required) Prevent the phone from sleeping so that an activated alarm will continue to go off.
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