Best open source apps for Android & iOS in 2017

Our mobile devices, particularly our smartphones, have practically become extensions of our persons. And yet we do not treat them with the same guarded vigilance as we do our homes. Whereas we, most often than not, scrutinize almost everything that comes or is added into our abodes, we willy-nilly install apps sometimes with wanton disregard for what they might contain. Granted, the ease of installing and sheer number of apps make it statistically impossible to scrutinize each and every one. Not to mention technically difficult if the app's source code is unavailable.Fortunately, there is a class of apps available under an open source license that makes it not only easier to inspect what gets installed on your phone but even take the app in new directions should the need arise. Here are some of the best open source apps for Android as well as iOS.

Why open source

But before we dive into those apps, it's worth noting first why we bother with open source software anyway. I'm not going into the philosophical and philanthropic benefits of free and open source software. That alone could take chapters to cover. Instead, I'd rather turn your attention towards the practical benefits that users can experience with open source apps on their phones. And, no, it's not about getting an app legally free of charge.


There's an oft quoted phrase in open source circles that goes "with many eyeballs, all bugs are shallow." That this means, at least in theory, is that with more people looking at a code, less bugs go through. Of course, this is not an absolute truth, as evidenced by some rather huge security flaws discovered in recent years involving open source software. But consider the possibility of how much longer those bugs would have been left undiscovered if the code were sealed shut by companies who prioritize saving face and profits over security and privacy.

The situation is easier with smaller apps like those you install on your phones. There will always be people curious or willing to look at apps, especially at suspicious-looking ones. And there are communities and repositories of open source apps that come with an implicit guarantee of security and safety.


Almost every smartphone user experienced falling in love with an app only to learn later on that the developer or company behind it has abandoned it, either for good or for greener pastures. In most cases, users have no choice but to use unmaintained and potentially unsecured software, if the app hasn't been yanked out of the Interwebs yet. Highly popular open source apps, however, are nearly immortal. Almost anyone can take up the torch or pass it on. They can even take it places the original author may have never imagined or intended. And it's all perfectly legal, too!


Open source software is a treasure trove for budding developers and creators. And that's all the more important these days as apps become the lifeblood of our digital age. More and more people are drawn to the app developer path, if not career, and it definitely helps if they have a lot of examples available to learn from.


All of these can practically be summed up in one word: freedom. Getting the app for free is really only a side effect of having the freedom to take the code and build it for yourself or for others. Freedom allows others to pick up were developers left off. Freedom allows users to continue enjoying an app long after it has been orphaned. And freedom allows you to install and use an app anywhere and any way you like it.

And now without further ado, here are our top open source pics for your beloved mobile device.

Top Android open source apps

F-droidF-droid is the Google Play Store of open source Android apps. While it's definitely possible or sometimes too easy to just download APKs here and there, or, at most, compile the source code, there's much to be said about having a single curated repository of open source apps. Especially one that lets you conveniently update them whenever new versions come. Definitely not the prettiest app store, but a new version is just around the corner, bringing a splash of Material Design with it.

Download: F-droid (APK), Source Code


Open source software don't always have a reputation for being the prettiest but what they lack in bling the more than make up for in power. FBReader is one shining example. Some might consider its appearance spartan, but others prefer the simplicity that belies its features. FBReader is the most widely available open source ebook reader, available on all major operating systems (except iOS) and supporting a wide variety of document formats. When tied with the open source Calibre e-book management software for desktops, you can pretty much run a ebook server of your own.

Download: F-droid, Google Play Store, Source Code


Many open source programs dare to tread murky legal waters, like the ever contentious market of game emulators. Given the closed, proprietary nature of platforms they have to work with, it's admittedly impressive when you see an emulator almost working perfectly with your favorite, legally owned, old game. Sony may have abandoned the PSP, but its rich collection of games is too good to pass up. Fortunately, PPSSPP is available on Android as well as other operating systems, letting you continue living those happy days even after your PSP has long bitten the dust.

Download: F-droid, Google Play Store, Source Code


Our smartphones have become our entertainment systems away from home and, just like any entertainment system, they're not limited to playing just music or videos. Some get their kicks from podcasts, be they the regular talk show kind or the more niche audio fiction. While many Android users might be content with using Google Play Music for their music needs, it's podcast support is lacking, not to mention unavailable in many markets. AntennaPod is a no frills, simple but powerful podcatcher that stays out of the way after you've done the initial setup. That setup involves either importing existing OPML playlists or browsing for the casts you love. AntennaPod includes features for both downloading and streaming audio and video, automatic updating and downloading of episodes, and integration with gpodder.

Download: F-droid, Google Play Store, Source Code


And when it comes to mostly video content, Kodi is the household name for home theater systems. Formerly known as XBMC, for XBox Media Center, Kodi is popular not only among open source enthusiasts but also among mainstream media junkies. Even Plex has partnered with Kodi to offer the ultimate DIY entertainment system. With a Plex server sitting somewhere at home, your Android device becomes a portal to your videos and even music anywhere in the house or, depending on the setup, even anywhere in the world.

Download: Google Play Store, Source Code


iOS 11 might finally be getting a file manager of sorts, but Android has had true file management capabilities from day one. That said, stock Android itself doesn't offer any such app to make that administrative task easier. Of course, there are a number of file manager apps out there, from OEM-made ones to powerful but ad-riddled ones. If you're looking for a capable, open source, ad-free solution, Amaze might amaze you. Pardon the pun. In addition to basic operations, Amazon includes facilities for browsing and backing up installed apps as well as running a mini file server to let you transfer files to and from another device via a local network.

Download: F-droid, Google Play Store, Source Code


Another kind of management task that Android supports but doesn't exactly make easy is storage space. By default, Android just gives you a broad overview of the categories of files that are eating up your precious limited internal storage. If you want a better but still visual idea of that information, DiskUsage will deliver it to you in boxes. Inspired by similar disk usage utilities from the desktop, DiskUsage visualizes data storage consumption as boxes whose sizes correspond to the percentage of space they take up. You can zoom in to get drill down into directories or even delete files right from the app.

Download: F-droid, Google Play Store, Source Code


It doesn't get geekier than this! A nod to Android's Linux roots, Termux gives you an honest to goodness command line interface on your phone or tablet. We'll leave out debates on the practicality of typing out those commands on a virtual keyboard, but if you're more comfortable fiddling with the precision of commands over multiple taps and swipes, this might be your cup of tea. Plus, with an honest to goodness package manager (apt), you basically have a system admin console and development environment with you anywhere you go. Bonus points if you're rooted!

Download: F-droid, Google Play Store, Source Code

Google I/O app

As mentioned, open source software is a great way to learn how to create software, and Google, being one of the largest users of open source software, only knows that too well. That is why year after year, it releases its Google I/O app as open source for Android app developers to take apart and learn from. This is basically the reference app for most of the features and design practices of what the Android platform has to offer.

Download: Google Play Store, Source Code (2016 version)

Top iOS open source apps

iOS is traditionally seen as a less open source friendly platform than Android, and that's not because it itself isn't open source, despite tracing its roots to the open source BSD operating system. For a time, Apple's iTunes App Store policies have been unfriendly, if not downright incompatible, with the biggest open source license in use. Things have changed a bit and while there still isn't as many such open source apps available, there are a few that bear mentioning.


It definitely took some time, but the most universal video player is finally available on iOS. VLC is on almost every major operating system and can play almost any kind of multimedia format. Its special trick on iOS is its Wi-Fi Sharing, that lets you copy files to and from your iOS device without having to connect via a USB cable and iTunes. It also supports iOS' split screen view for the ultimate productivity, or anti-productivity, workflow.

Download: iTunes App Store, Source Code


Open source users are, more often than not, more conscientious of privacy and security issues than your regular consumer. But with the recent spate of news about hacking and spying, there's an increase in interest in keeping private communication private. If you're looking for a super private messaging app, look no further than Open Whisper Systems' Signal. Used by advocates around the world, as well as whistleblowers like Edward Snowden, Signal promises an attention and commitment to privacy that no for-profit company can afford.

Download: iTunes App Store, Source Code


iOS is pretty restrictive towards third-party browsers, restricting them to use only its WebKit engine. That's one reason why it took so long for Firefox to be officially available on Apple's mobile devices. And it's also one reason why there are rather few unique web browser apps there as well. Brave is one of the new and upcoming web browsers for desktop and mobile. Started by Mozilla co-founder and Javascript creator Brendan Eich (and, ironically, using Chrome's engine), Brave puts privacy at its core rather than as an add-on. It's pretty much like Mozilla's new Firefox Focus browser, except it's a regular, full-feature web browser as well.

Download: iTunes App Store, Source Code


Tired of your boring, not to mention overwhelming, todo list app? Want to add a bit of fun to building habits? Fancy yourself as some sort of hero? If you answered yes to any or all of those, then Habitica is going to tickle your fancy. Formerly known as HabitRPG, this tool employs the ideas of "gamification" to add a bit of flavor to your todos and habits, turning it into something like a fantasy role-playing game, earning points and gears as you complete goals. You can even team up with other users both for accountability as well as motivation.

Download: iTunes App Store, Source Code


Evernote is arguably the granddaddy of note-taking apps and services but it has recently fallen out of favor even among its staunchest fans. Microsoft OneNote doesn't suit everyone's workflows, Apple Notes is, well, Apple-only, and Google Keep is better for Post-it style notes. If you need a clean and simple, text-based note-taking solution that still has the benefits of something like Evernote, with cloud syncing and revision history, then Simplenote, made by the same people behind WordPress, will definitely fit the bill. Of course, it's available everywhere, so you can take your notes anywhere with you.

Download: iTunes App Store, Source Code


This is definitely just the tip of the iceberg and there are countless open source apps out there with varying designs, purposes, and qualities. Not all of them are great but there are definitely some shining examples of both technical wizardry and tasteful aesthetics. Not all of the best apps are found in Google Play Store or iTunes App Store, so don't be afraid to sometimes do wander off the beaten path a bit. Of course, just because it's open source doesn't exactly mean it's bug-free or malware-free. As long as you keep your wits about you and follow security best practices, the world of open source apps holds hidden gems for your mobile device. So be free and enjoy the freedom!