Productivity
1843 open source Productivity apps
Isotope Browser
APK
Provided by the Nuclear Data Section of the International Atomic Energy Agency, Isotope Browser gives properties of more than 4 000 nuclides and isomers.A Chart of Nuclides, with zooming and tapping enabled, and a Periodic Table of Elements are included to allow easy selection and navigation.Filter criteria on half-life, decay mode, radiation type and energy can be selected.Summary data are presented in a scrolling list, with a details page for each nuclide containing web links to the data sources and further information.The filtered nuclides can be visualised on the Chart of Nuclides.Data are taken from the most recent and reliable sources, and optimal search-and-retrieve performance is achieved with an embedded database, meaning that no network connection is required.
GitHubIzzyOnDroid
Isotopes
APK
Isotopes is an app with more then 3000 isotopes, both natural and synthetic, including accurate mass information and natural abundance.
F-DroidGitHub
Itinerary Planner
APK
Itinerary Planner is designed to make your travel planning easier and more productive. Features: * Plan Management - Create, view, and manage multiple travel itineraries * Task Scheduling - Add tasks with start/end times and duration * Cost Tracking - Track expenses for each activity and overall trip budget * Open-source - The source code is distributed under GNU GPLv3 * 100% free and No ads - We do not charge any fee or sell ads Source Code: The source code is available at the following GitHub repository: [https://github.com/pixelarry/itinerary_planner]
F-DroidGitHub
IzzyOnDroid (unofficial)
APK
IzzyOnDroid is an unofficial client for IzzyOnDroid F-Droid Repository. Features - Elegantly designed user interface. - Option to categorise applications. - Includes an in-built APK installer. - Update notification service. - Dark/light themes. - A lot more.
F-DroidIzzyOnDroid
J-K Bike - Mechanical Disaster Prevention
APK
We have all experienced those rides where something mechanical happens that really was preventable. As the authors, even though we take a certain pride in our own efforts in maintaining smooth running MTBs, and a disdain for our riding buddies who never give a passing thought until something goes 'CRUNCH!' in a ride-ending manner, there are still innumerate situations where something that should have been checked, or usually never needs checked after proper installation, has not been. 'Where is that vibration coming from?', 'why is the rear end creaking?', 'What is that terrible knocking?' are so often result of something relatively simple being overlooked or forgotten. Recent favourites have been disc rotor bolts backing out, rear thru axles not done up properly, and headsets improperly tensioned. So, to prevent mechanical disasters happening on your rides, use this app to build better, new, habits and ensure your rides are (mechanically) glorious. The app can connect ot Strava and update mileages/distances as well as last ride dates. This app uses INTERNET and ACCESS_NETWORK_STATE permissions to download template activities from a github repository at https://github.com/janexner/JKBikeTemplateActivities, and to retrieve data from 3rd-party integrations, currently with Intervals.icu only. No internet access beyond that.
F-Droid
J
JABtalk
APK
JABtalk is a free speech communication application designed to help non-verbal children and adults communicate. Speech therapists commonly refer to JABtalk as an easy and effective augmentative and alternative communication (AAC) device. By combining personalized voice and images with an extremely simple user interface, JABtalk delivers a speech solution that is both fun to use and easy to learn. Originally designed as a communication tool for children with special needs, JABtalk has evolved into a communication tool used by special needs children, stroke patients, toddlers, speech-language pathologists, and others.Some of JABtalk features include…Navigation designed to be intuitive for toddlersBuild sentences from wordsOrganize words into user-defined categories for simple navigationHeptic feedback (vibration) when touching a word or category for immediate physical feedbackAbility to rearrange and resize picturesDownload unlimited number pictures from internet directly into JABtalk!Ability to capture pictures directly from your device’s cameraAbility to import pictures from your device’s memory cardAbility to record your own audio for words using your devices microphone.Ability to import audio files from a memory cardSupports text-to-speech if you don’t want to record or import your own audio filesEasy to use passcode protected administrative tools for managing words and categoriesFullscreen mode to prevent kids from easily exiting appEasily backup/restore your data to preserve your changes or move your entire dataset to a different deviceOnline tutorials at https://www.jabstone.com/videosIf you are using JABtalk as an AAC device for an individual with special needs (down syndrome, autism, etc...), we strongly recommend having the individual assessed by a speech-language pathologist to ensure JABtalk is the most appropriate solution for the the individual’s needs.
GitHubIzzyOnDroid
J
JKU App
APK
This is an app for the students of JKU Linz that provides most of the data from KUSSS and also information from ÖH and the JKU in general: * synchronize timetable with local or Google Calendar. * access Exams, Grades, Courses. * get notifications for new exams, grades and changed course dates * included campus map for "navigation" * shows menu for JKU Mensa, Raab Mensa and KHG Mensa
F-DroidGitHub
JMdict droid
APK
Search for English definition of Japanese words using kanji, kana or rōmaji. Search for Japanese words from their English definition. Basic wildcards are supported, to search for incomplete words, words ending with a specific kanji, etc. JMdict data is not included in the APK. It must be downloaded (or loaded from a file) from the application first. Afterwards, the application is completely standalone and can be used offline. JMdict is provided by Electronic Dictionaries Research Group. See https://www.edrdg.org/
F-DroidGitHub
JRBP Survey
APK
The Jasper Ridge Biological Preserve ant survey regularly surveys the species of ants in each of hundreds of locations across the preserve. This application helps people navigate to the correct locations, identify ants, record observations, and upload them to a central database. Note: This application is intended only for registered volunteers participating in the ant survey. For more information about the ant survey, see https://jrbp.stanford.edu/research/jrbp-ant-survey .
F-DroidGitHub
JRPN 15C
APK
JRPN 15C is a scientific calculator that simulates an HP-15C. It simulates the appearance and behavior of the original, including the seven-segment display, and the little blink you get when entering numbers. Includes complex math, matrices, numerical integration, solving for the root of an equation and statistics. Very state of the art for 1982!
GitHubIzzyOnDroid
JRPN 16C
APK
JRPN is a programmer’s calculator that simulates an HP 16C. It simulates the appearance and behavior of the original, including the seven-segment display, and the little blink you get when entering numbers. The 16C’s windowing functions are implemented, but can be disabled to allow the display of longer numbers at one time.
F-DroidGitHubIzzyOnDroid
JS-Dict
APK
JS-Dict is a convenient app for accessing the powerful Japanese-English dictionary Jisho.org. This app is Free and Open-Source Software. The source code is available at https://github.com/petlyh/JS-Dict.
F-DroidGitHub
JSlab
APK
The author was in need of a more capable calculator app than what's included with Android. After finding none that pleased him he made one himself. Javascript is turing complete, WebViews provide javascript and the eval() function. Thusly JSlab was created.
F-DroidGitHub
Jamu
APK
An app to help learn Japanese. Features Gojuon (五十音) Numbers (数字) NHK Easy News Quiz Trivia (豆知識)
F-DroidGitHub
Japanese Traditional Time
APK
A clock widget based on the traditional Japanese time system. * Widget showing the current hour (named after an animal) * Mapping of traditional time to local time * (Eventually) Alarms based on traditional time The sunrise and sunset times for are calculated locally by the app for the current location; if the device doesn't know that you can enter a manual one.
F-DroidGitHub
Java OOP Quiz
APK
Java OOP Quiz App is an interactive mobile app designed to help users test and improve their knowledge of Object-Oriented Programming (OOP) concepts in Java. It features a variety of quizzes that cover essential topics like classes, inheritance, polymorphism, and interfaces, with immediate feedback to enhance learning. The app includes a smooth user interface and progress tracking.
F-DroidGitHub
JetSpacer
APK
JetSpacer pulls data from multiple NASA APIs and wraps it all in a minimal UI.Features:Custom pagination for APOD Archive, Mars Gallery, and Headlines.Search APOD, Mars Rover Photos, and NASA Image Library.EPIC shows latest Earth imagery.Bookmarking for APOD and Mars Rover Photos.Caching support for Headlines with manual clear option.Default API key included (or use your own: NASA API Signup).
GitHubIzzyOnDroid
Jiten Japanese Dictionary
APK
Jiten is a Japanese dictionary based on JMDict/Kanjidic This is the offline android version of https://jiten.obfusk.dev. The large download size is because it includes all the dictionary data, including audio. NB: the app will take a while to load the first time it is started (or after an update), but it will load a lot faster afterwards. Features: JMDict multilingual japanese dictionary • kanji, readings (romaji optional), meanings & more • meanings in english, dutch, german, french and/or spanish • pitch accent (from Wadoku) • browse by frequency/jlpt Kanji dictionary • readings (romaji optional), meanings (english), jmdict entries, radicals & more • search using SKIP codes • search by radical • handwritten kanji recognition • browse by frequency/level/jlpt/SKIP Example sentences (from Tatoeba) • with english, dutch, german, french and/or spanish translation • some with audio Stroke order • input a word or sentence and see how it's written Fine-grained search using regexes (regular expressions) • simple searches don't require knowledge of regexes • quick reference available • Dark mode • Search history (stored locally) • Use long press for tooltips: quickly see meanings and readings for kanji and words • Easily share and open jiten.obfusk.dev links • Convert romaji to hiragana and between hiragana and katakana No ads. No trackers. The source code is 100% Free and Open Source (AGPLv3+) and the data is available under Creative Commons or similar licenses (some non-commercial); for details, see https://github.com/obfusk/jiten#readme To report bugs and request features, please use the issue tracker at https://github.com/obfusk/jiten/issues Questions and feedback are welcome at https://github.com/obfusk/jiten/discussions or jiten@obfusk.dev
F-DroidGitHub
Jiten Japanese Dictionary [Online]
APK
Jiten [Online] is a Japanese dictionary based on JMDict/Kanjidic This app essentially provides the same functionality as opening the https://jiten.obfusk.dev website in a web browser — but with some small advantages (like long press for tooltips). There is also a completely offline version — named simply "Jiten Japanese Dictionary" — which requires more storage space (and could be slower depending on your device and internet connection). You can install both at the same time if you want. Features: JMDict multilingual japanese dictionary • kanji, readings (romaji optional), meanings & more • meanings in english, dutch, german, french and/or spanish • pitch accent (from Wadoku) • browse by frequency/jlpt Kanji dictionary • readings (romaji optional), meanings (english), jmdict entries, radicals & more • search using SKIP codes • search by radical • handwritten kanji recognition • browse by frequency/level/jlpt/SKIP Example sentences (from Tatoeba) • with english, dutch, german, french and/or spanish translation • some with audio Stroke order • input a word or sentence and see how it's written Fine-grained search using regexes (regular expressions) • simple searches don't require knowledge of regexes • quick reference available • Dark mode • Search history (stored locally) • Use long press for tooltips: quickly see meanings and readings for kanji and words • Easily share and open jiten.obfusk.dev links • Convert romaji to hiragana and between hiragana and katakana No ads. No trackers. The source code is 100% Free and Open Source (AGPLv3+) and the data is available under Creative Commons or similar licenses (some non-commercial); for details, see https://github.com/obfusk/jiten#readme and https://github.com/obfusk/jiten-webview#readme To report bugs and request features, please use the issue tracker at https://github.com/obfusk/jiten/issues Questions and feedback are welcome at https://github.com/obfusk/jiten/discussions or jiten@obfusk.dev
F-DroidGitHub
Joplin
APK
Note: This release can lag significantly behind the official release which can be an issue when a timely update is needed. It may be less secure because the app might have a known security vulnerability for several days, even if the official app has been patched. It does not have camera capabilities nor location functions. Issues with this version might be raised on https://gitlab.com/fdroid/fdroiddata for user @muelli Joplin is a note taking and to-do application, which can handle a large number of notes organised into notebooks. The notes are searchable, can be copied, tagged and modified either from the applications directly or from your own text editor. The notes are in Markdown format. Notes exported from Evernote and other applications can be imported into Joplin, including the formatted content (which is converted to Markdown), resources (images, attachments, etc.) and complete metadata (geolocation, updated time, created time, etc.). Plain Markdown files can also be imported. The notes can be securely synchronised using end-to-end encryption with various cloud services including Nextcloud, Dropbox, OneDrive and Joplin Cloud. Full text search is available on all platforms to quickly find the information you need. The app can be customised using plugins and themes, and you can also easily create your own. The application is available for Windows, Linux, macOS, Android and iOS. A Web Clipper, to save web pages and screenshots from your browser, is also available for Firefox and Chrome.
F-DroidGitHub
Journal
APK
PsychonautWiki Journal can help you keep track of your substance use and give you insights on your consumption patterns. The substance info comes from PsychonautWiki with some additional info from Tripsit and saferparty.ch The app is designed to work fully offline. The data you enter in the app never leaves your device.
F-DroidGitHub
Just 24 Hours
APK
When all you need is to know what time it is, only the actual time matters. There are many wonderful clock applications available for Android devices. Many have have lots of great features. Choice in applications is a good thing. When one wishes to choose a simple clock application that just displays the time of day in as large numbers as can fit on the screen's device, Just 24 Hours is here! '''Features:''' Just 24 Hours will display the time of day in 24 hour format in a big numbers as will fit on the screen. For those that were corrective lenses, it can be challenging to read small numbers when just waking up. Big numbers are required. No matter what size screen your Android device has, Just 24 Hours will use as big a text size that will fit on the screen. That is all. No alarm settings. No typeface settings. No colour settings. Just a big clock to see what time of day it is. Of course, this is not what everyone wants in a clock application. This is okay. There are dozens of clock applications available for Android. Most (maybe all!) are great applications. We are certain that there will be one that will satisfy one's desired features. For those that just want the time, Just 24 Hours is here!
F-Droid
Just Another Workout Timer
APK
* Create complex workouts easily * Define your own exercises with custom durations * Add exercises to custom sets * Text-to-Speech announcements * Modern Material Design built with Flutter * Ad-free * Free and Open-Source Github: https://github.com/blockbasti/just_another_workout_timer
F-DroidGitHub
Just Sit
APK
JustSit is designed to help you meditate. It currently runs timers for preparation to meditate and meditation, and allows you to turn off audible ringing and/or the device radios, and keep the screen on while the timer is running. The name is inspired by the saying, "If you walk, just walk, if you sit, just sit, but whatever you do, don't wobble." -Zen Master Unmon
F-Droid