UI = User Interface UX = User eXperience
Most open source apps offer out-dated or classic material design UI. If the apps works great and the UX is not terrible you might find it okay. But intuitive UI are better, and modern looking ones are pleasant to use, sadly they are not the majority. Here is my list of Beautiful Open Source Apps for your android device !
Also look at : The ultimate F-Droid setup for more open source android apps. and Beautiful Open Source Apps for iOS for your iOS device
Nice UI comes to personnal preference. So this list is only based on my taste of what is a good modern looking app.
While open source is great for privacy and security it is not perfect. So keep that in mind before downloading any apps. I again encourage you to do your own research about them and read their Privacy Policies.
I am not a privacy and security expert. I'm also don't consider myself as a developper so I do not have any technical knowledge and so I didn't look into any source code of any apps in this list !
Aegis Authenticator is a free, secure and open source app to manage your 2-step verification tokens for your online services.
Aegis is my go to for 2FA based on TOTP. The UI is modern and intuitive while being secure and private. You will have to download an icon pack for having icons instead of letters for your differents icons. The app explain you how to do it !
A lightweight FOSS Android launcher forked from AOSP's Launcher3, using yuchuangu85's repo as a base.
podium is a modern, open-source Podcast app for Android, written in Kotlin using Compose. The app uses Material 3 Expressive design to fit right in with modern Android UI.
An open-source Android app built around flexible workspaces and customizable spaces—enabling you to organize notes, journals, tasks, events, and more, while adapting to your own systems as it evolves.
Traffic Light is an open-source tool for tracking your network usage while ensuring total privacy. Inspired by Internet Speed Meter and GlassWire.
Peri is period tracker application. The application has the necessary features that help you track your cycle. The app shows:
Whether you're maintaining sobriety, breaking harmful habits, or building positive routines, Grove helps you stay focused on consistent progress. Watch your streaks grow, track meaningful milestones, and cultivate a forest of procedurally generated fractal trees that evolve...
Premium audiophile grade offline music player with native DSP, Visualizer, 10-Band Equalizer with PreAmp and Milkdrop support, currently in initial alpha testing.
Apple’s messaging network has gained a lot of popularity in recent years, though it has long been locked down to their platforms. But now, AirMessage makes it easy to send and receive messages to your friends and family through group chats, images, videos and audio messages!
This app let you use iMessage on your Android device ! (A Mac computer is required)
Record in the background and save only the last 30min if needed
Open source file utility for Android with built-in media players, file transfer over Wi-Fi, storage analyzer, image grouping, and no advertisements.
A free and open source podcastmanager for Android, allowing you to subscribe to podcasts (via iTunes database & OPML), automatically download episodes using powerful mechanisms and listen to them the way you like (speed, balance adjustments, etc).
The new MaterialYou version of AntennaPod is just gorgeous !
A really good open source podcast app !
Athena is a Material You (Material 3) firewall and ad blocker that works seamlessly on both rooted and non-rooted devices.
A beautiful and modern periodic table in your pocket !
Open-source Android app recognizing music via AudD and ACRCloud, storing results with full metadata, lyrics, and links, supporting offline use and robust library management.
An open source feature rich shazam alternative
Streams music from YouTube Music on Android, supports playlist creation, background playback, song search, lyric display, favorites, and downloads.
Identifies music around you, showing title, lyrics when available, album info, and quick links to streaming platforms, while saving your recognition history.
Shazam but open source
Aurora Store enables you to search and download apps from the official Google Play store. You can check app descriptions, screenshots, updates, reviews, and download the APK directly from Google Play to your device.
Download app from
Google Play Store without a Google Account. Or sign in with your Google account for downloading your paid apps on a degoogled phone
Aves can handle all sorts of images and videos, including your typical JPEGs and MP4s, but also more exotic things like multi-page TIFFs, SVGs, old AVIs and more!
A nice gallery app
Your one-stop solution for watching anime and reading manga! Packed with powerful features, a sleek UI, and tons of customization options.
A modern looking manga reader and anime app
An open-source app that allows you to read and generate barcodes for Android.
The best QR code scanner app on Android
A cup of coffee is not the same anymore then back in the 80's, thats why I wanted to build a tool for the coffee community.
🎉 A beautiful Kotlin app to remember birthdays and events without having to open Facebook, set alarms or rely on Google Calendar.
A birthday remember app that is well made and have a modern UI.
Open-source password manager with AES-256 encryption and device sync. Store and access encrypted logins across platforms like iOS and Android.
The FOSS cross-plateform password manager !
Note : You SHOULD use a password manager.
Bitwarden Authenticator generates verification codes for two-factor authentication, ensuring your identity is verified when you log into accounts.
A standalone open source TOTP app from BitWarden Password manager
Experimental open-source player offers ad-free music streaming from multiple platforms like YouTube and JioSaavn, enabling seamless source switching and cross-device use.
An ad-free YouTube music client
BMI Calculator is a Body Mass Index(BMI) calculator app developed with Flutter. Currently, the BMI is calculated using Metric units. Support for Imperial units may be added in the future. The app supports English and Turkish languages.
Beautiful UI to quickly calculate your Body Mass Indicator !
Material3 eBook reader - Book's Story. Built with Jetpack Compose. Free & Open Source & Ad Free. 4 supported file formats (.txt, .pdf, .epub, .fb2), 2 supported languages. Lots of customization.
A beautiful eBook reader
Modern music app for Jellyfin servers offering album downloads, offline listening, configurable storage, cross-navigation, search, and artist recommendations.
A modern and sleek music player for your
Jellyfin server.
Fast, secure browser with built-in ad block, privacy controls, and global tracking protections. Optimizes data, speed, and battery life.
One of the best web browser for Android. Block ads and trackers by default and as good privacy default configuration ! I do not use the BAT cryptocrap stuff.
Breezy Weather is a weather app with a strong focus on design, with a simple, clean UX, smooth animations, and Material Design all over, plus lots of customizability.
A nice looking weather app (active fork of Geometric Weather)
Bura transforms and visualizes weather data from Open-Meteo.com to give you essential weather information at a glance, while allowing you to dive deeper with graphs.
Weather app with graph based on Pognoza
THIS IS NOT FINANCIAL ADVICE !
If you want to learn more on how to buy, store and use crypto the right way to empower your sovereignty and/or privacy look at my other list Doing crypto the right way ! A great looking multi-cryptocurrencies wallet with some privacy feature and support for
Monero ,
Bitcoin ,
Ethereum ,
Litecoin and Haven (XHV) + the stable coins Haven protocol supports and NANO.
Note : if you want a XMR only version of this wallet look at
Monero.com it's also from Cake Labs devs.
Calculator-inator is a Calculator & Converter for Android inspired from 
Google Calculator
A beautiful open source calculator inspired by
Monitors battery levels for AirPods, Beats, and compatible models on Android with pop-up notifications, widget support, and premium features unlock via F-Droid.
If you use AirPods !
Tracks expenses, budgets, and subscriptions with offline access, privacy focus, CSV import, visual analytics, multi-currency features, and no ads.
A beautiful expense and budget tracker for mobile.
A gorgeous modern feature packed clock app
Beautiful, minimal, and fast weather app that uses the OpenWeatherMap API. (Requires Android 6.0 or later)
One of the most beautiful open source weather app IMO
CoinWatch is a cryptocurrency app providing real-time coin prices, price histories, and market data, built using the latest Android architecture components.
To look at your favorite crypto prices in dirty fiat (USD)
Unlike other apps that use slow, bulky, old versions of FFmpeg with software encoding, Compressor uses Android's native Media3 Hardware Acceleration to process video faster than any other app.
Cromite is a Chromium fork based on Bromite with built-in support for ad blocking and an eye for privacy.
A bromite continuation, privacy focused foss chromium browser
“Data Monitor" is a user-friendly, free and open source app for you to manage your data usage. “Data Monitor" helps you to accurately measure your daily data traffic, and analyze the data in a way easy to understand.
Show data consumption with a great UI
DioHub is an open-source unofficial GitHub mobile client, that aims to deliver the ultimate GitHub experience on mobile devices.
A GitHub client for Android
A menstrual cycle tracking app that's open-source and leaves your data on your phone. Use it to track your menstrual cycle and/or for fertility awareness!.
The best looking open source and private menstruation tracking app available.
Note : F-Droid package is outdated. If you know how to make one join their GitLab !
Open Source doesn't mean ugly
Comments
Thanks for sharing! Will check some of these out!
I'd also add Element(.io) it's pretty much Signal privacy with Discord type of features and it's decentralized. I think it has better security than Signal.
edit: Ended up leaving Buttercup for KeepassXC so nvm that
But nice list! Saw some apps that i haven't heard of so I'll look into those.
You right I've forgot Element. It's not better than Signal tho, it's a different usecase. Never heard of Buttercup, will look into it.
Happy to hear that you discover new apps, I hope you'll like using them !