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 !
If you use multiple browsers on Android 12+ this might come handy as it is a browser selector.
Free open-source tool offers secure, end-to-end encrypted file and message sharing over local networks across major desktop and mobile operating systems.
AirdDrop but crossplateforme and over local network
Locus is a free, open source app for Android and iOS that allows you to share your location live. It encrypts your location end-to-end, meaning that no one, not even we, can read it. It stores the location decentralized on multiple servers of your choice using Nostr, meaning...
Share your location with e2ee and decentralized censorship-resistant Nostr relays !
A gorgeous modern yet simple local music player
Federated and open-source social network with no ads, 500-character limit, custom emojis, and content warnings, emphasizing privacy and personal interaction.
The official mastodon client is really well made ! It's a federated alternative to
X
100% Free Meditation App that will improve your Mental wellbeing with the help of Guided Meditations, Breathing Exercises, Mindfulness Practices, Relaxing Sounds, and more.
Menstrudel is a simple, private, and intuitive mobile application built with Flutter to help you manage your menstrual health. Log your period dates, record symptoms, and track flow intensity with ease.
Messages is an open source replacement to the stock messaging app on Android. It is a continuation of 
QKSMS.
To download and read manga
Mindful is a free and open-source app designed to help you regain control over your digital habits, improve your focus, and boost productivity. Whether you're battling social media addiction, struggling to stay focused, or simply looking for a way to better manage your...
The open source Phone-detox app-blocker app to regain focus and reduce screen time
A beautiful local music player inspired by NothingOS design
A fully functional app for tracking personal expenses built using Jetpack Compose with a simple UI for easy understanding and ease of use.
mpvExtended is a fork of mpv-android, built on the libmpv library. It aims to combine the powerful features of mpv with an easy to use interface and additional features.
A lightweight nice looking music player for your device.
All-in-one Open-Source productivity app and AI assistant with Tasks, Notes, Calendar, Diary and Bookmarks.
An all-in-one productivity app !
Myne is a FOSS Android application to download ebooks from the Project GutenBerg, it uses GutenDex API to fetch metadata of ebooks in the backend.
A beautiful Material You free eBook downloader for Project Gutenberg.
Music and video player built with Flutter, offering YouTube playback, folders-based indexing, powerful tagging, offline caching, dynamic themes, and advanced queue management.
A beautiful and quite unique music player that embed a youtube player
A minimalistic notes app. Notally it's extremely light, minimalistic and elegant. There are minimal dependencies and lines of code. (All without compromising on readability).
One of the best looking offline note taking ! Also a super minimalist app !
Gallery for Nothing Phone with effort to follow the Nothing Design Language.
A Gallery app inspired by NothingOS design.
Noto is an opensource minimal Note-Taking app that meets customer expectations with privacy in mind.
A beautiful, feature rich and privacy focused yet minimalist note taking app !
If you run an ollama instance at home this make it cool to interact with your phone
A beautiful MaterialYou compass with minimalist toolbox feature
Lightweight calculator app for Android featuring scientific mode, multiple themes including Material You, calculation history, and minimal permissions for privacy.
My personnal calculator app, simple and amazing black AMOLED theme !
OpenJot is a minimal and open-source journaling app designed for privacy and simplicity. All your thoughts, memories, and ideas are stored securely on your device, never in the cloud.
Openlib is an open source app to download and read books from shadow library (Anna’s Archive). The App Has Built In Reader to Read Books.
A modern eBooks downloader and reader
OpenNutriTracker is an open-source mobile application designed to simplify nutritional tracking and management. Whether you are looking to improve your health, lose weight, or simply maintain a balanced diet, OpenNutriTracker provides a minimalistic interface to easily track and...
An open source app to eat better
Keep track of your readings with this beautiful app
The ultimate home for modded apps. OrionStore offers instant access to YouTube ReVanced, Spotify Premium, and essential open-source tools without the clutter. No servers, no tracking, just a beautiful, modern gateway to the apps you love.
The OSS Document Scanner is a free and Open Source app to transform your mobile device into a powerful document scanner.
For having a pocket document scanner that don't spy on your files
PACE is a secure fitness tracker for iOS and Android. Your fitness, health, geolocation data and preferences are end-to-end encrypted (E2EE) before being saved. This guarantees that only you can view them.
A nice looking e2ee fitness tracker app
Paperize is a dynamic wallpaper changer application built for Android using Kotlin, Jetpack Compose, and Material 3.
A feature rich wallpaper app
Privacy-first PDF utility (Zero-Server Architecture). Merge, split, compress, and edit PDFs 100% locally on your device. No uploads, no servers, no tracking.
PhotonCamera uses advanced algorithms for capturing and processing raw images which give unmatched HDR outputs.
A great open source camera app for mobile photographer
PixelPlayer is a modern, offline-first music player for Android, built with Kotlin and Jetpack Compose. It's designed to provide a beautiful and seamless experience for listening to your local music library.
Pixy is a free, open-source mood tracker for iPhone and Android. Log moods, add notes and tags, and explore your history in a pixel calendar.
A great minimalist mood tracking app.
All-in-one Android podcast app for RSS, media dl & play. MVI arch, Material You style. ?? Star to support!
A podcast app with RSS feed
An elegant and colorful location information app for Android with Compass, Clock, Level, Sun, Moon, Trail Marker and many other features.
A modern, feature-rich, and lightweight file manager for Android, built entirely with Kotlin and Jetpack Compose. Also features a text editor with syntax highlighting for java, kotlin, xml and json files.
A beautiful file manager made with native Jetpack Compose and Kotlin
A beautiful bold weather app with great widgets !
Secure Swiss-based email with end-to-end encryption and zero third-party access. Available across devices, offering a free version to promote privacy.
Proton Mail is an encrypted e-mail provider, the official client has a really nice UI.
QUIK is an open source replacement to the stock messaging app on Android. It is a continuation of QKSMS.
The best open source SMS client for Android in my opinion based on QKSMS !
This application allows you to view the weather in your city. The following options are provided:
Another gorgeous looking weather app with a cute style.
🎲 An open source app to choose randomly between numbers, answers, options and so on. - m-i-n-a-r/randomix
If you need to make choices or rolling dices
This is a copy of Reeder, in order to give Android an RSS reader similar to Reeder, combines the interaction logic of Reeder with the design style of Material Design 3 (You).
RSS feed reader with nice UI/UX !
ReTerminal is a sleek, Material 3-inspired terminal emulator designed as a modern alternative to the legacy Jackpal Terminal. Built on Termux's robust TerminalView.
The best looking local music player for Android. Note : Freemium, free version is complete and paid version is advanced :)
You can also use
Metro - A music player for Android which is a fork of Retro premium for free, it can lack behind updates. And paying Retro supports the project. Do your choice ;)
Or the Airsonic/Subsonic compatible fork
Retro Sonic Player
The ultimate app for organizing and customizing your contacts with a focus on privacy. Take control of your contact list by creating private contacts that are accessible only within the app, ensuring that your personal information remains confidential and secure.
Apple iOS inspired contact app
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 !