My banking app ಠ_ಠ

Pedantic, but Google Messages' RCS. And it's all Google's fault because they are holding the API hostage, probably because they want to create familiarity with the app so that people don't switch once they finally open up.

Google Pay/Wallet

Right now tap and pay is completely and hopelessly corporate

Google Play Services

A keyboard with swipe typing, multilingual autocorrect and speech to text support that actually works.

Other than that, my only proprietary apps are from commercial services I use and pay for (banking, Spotify, Carsharing and public transport). I'd love for them to become open source, but it's probably not ever gonna happen, cause they rely on verifying my identity.

I'm not sure if this fits but here is mine:

I want to get away from Samsung but the "Sound Assistant" app let's me control the volume of every app, kind of like a mixer. Sometimes an app doesn't have a mute option, I can set the volume of that app to 0 without effecting the volume of whatever music I'm listening to.

I also like to listen to my local police scanner and music at the same time. I can set the volume of the scanner app low enough to not really bother the music but loud enough that if something happens I can still hear it and pause the music.

I can't believe Samsung and their app is the only way, but I haven't found an alternative.

Tasker, because there's no alternative.

MiXplorer (file manager), because even if not counting the features that should be a different app, it's much better than material files.

Obsidian

Tasker: I haven't used it, but I've seen useful automations over the years from people online and I would probably use a good FOSS alternative.

Symfonium. There are plenty of music apps, and I've used a lot of them, but none combine the UX and functionality that Symfonium offers to anywhere near the same quality :/

File Manager Plus:

It connects to all my SFTP servers effortlessly, and it's an absolutely stellar file Manager.

JuiceSSH:

Manages all my SSH servers and identities, and has an extremely usable terminal. It's got extensions too.

OpenCamera is good, but could do better. But I'd say video editing is the biggest void.

Also, gesture typing keyboards are an empty niche of foss alternatives. HelioBoard requires loading some proprietary blob unfortunately.

I guess the most heavy machine learning use cases are not filled in.

People have hit on most of them here, but here is another big one:

Fitness apps. Mainly calorie tracking, workout tracking and heart rate tracking

Health app

Sleep as Android

(No, gadget bridge is not a replacement for 99% of cases and doesn't even support the gold standard for heart rate tracking, polar H10)

For calorie tracking, the massive food databases required, barcode scanning, and crowd sourcing are generally not compatible with the open source community's privacy ideals. OpenNutriTracker has promise though!

For workout tracking, none of them have any device support and most of them are dead and abandoned. Not to mention heart rate zones, stats and training trends, etc... FitoTrack and Opentracks are good starts though.

And then a google fit alternative. Something that can integrate sleeping, workouts, heart rates, sensors, etc.. Data all in one aggregates place. It is a huge task and it makes sense that there is no open source alternative for it. Especially when the components aren't individually there to aggregate.

I really need a libreoffice calc on my android phone. Not just opening (where currently only Microsoft Excel on Android works for me) but also editing and saving to my connected nextcloud (where I have also problems with Excel)

I'm actually pretty happy to be using mostly FOSS apps. The exception are banking or services apps, which I'd never expect to be available as open source.

I would like to find alternative to Garmin app. It is bad if you don't want to use the cloud features, also you can't plan routes without internet connection like wtf that's the only reason I bought it for.

Basically every app that is related to a proprietary service. Amazon, Battle.net and Steam authenticators, banking apps, Spotify, etc.

All these mouse cursor touchpad for big phones-apps. They seem pretty easy to do and are quite handy.

There already was a post like this this year but now my answer is "a standardized push notification system (most likely federated) that's actually possible to be implemented in a user friendly way". Google doesn't want to encrypt theirs afaik and apparently some people are concerned about the traditional "every app is responsible for its own notifications" approach consuming much more battery, even though I didn't notice it myself (I guess it's possible if you have 50+ apps installed but it's not something that should be a thing in the first place).

Maybe Niagara Launcher, though I'm quite happy to pay the dev a bit of money (not required for most stuff actually, I only login on my phone)

Until recently I'd have said Symfonium for music playback from Jellyfin, but the Finamp beta gave me an OSS alternative.

Ideally banking apps, booking.com and TripAdvisor all had FOSS alternatives, but that's not realistic.

The default Samsung messages app. It allows custom backgrounds for each text conversation. All apps I find only allow custom colors, no custom wallpaper. Eben Google messenger had this feature... Then they took it out and replaced it with pre selected 'color themes'

Bank clients. Taxi aggregator clients.