Serento: The audiophile UPnP controller app for iOS/macOS

[serento]

Hi everyone.

I was asked by simoncn to create a new thread so here goes.

Disclosure first: I'm the developer of the app I'm about to describe. I'd rather be here answering questions than advertising, so ask me anything technical and I'll give you a straight answer.

I've been an audiophile far longer than I've been writing this particular app. I run the largest audiophile community in Romania, I review gear, and like most people reading this I've spent years getting a digital front end to a place I'm happy with. Separately, my day job is running a small iOS development studio.

For a long time those two things stayed in separate boxes. What finally brought them together was the frustration I suspect a lot of you know well: the hardware kept getting better, and the app I held in my hand to control it didn't. I'd sit down with a system I'd spent years assembling and drive it with something slow, that lost my place the moment I picked up a different device, that couldn't play half my DSD library locally, and that dropped the radio stations I actually listen to.

At some point it stopped making sense to keep complaining about it when writing iOS apps is literally what I do for a living. So I built the control point I wanted for myself. It's called Serento, it runs on iPhone, iPad and Mac, and it's now on the App Store.

The one principle I refused to compromise on: it stays out of the audio path. Serento finds your server and your renderer, tells them to talk to each other directly, and steps aside. It never proxies the stream and it never modifies your files - corrections and artwork layer on top, inside the app, never written back to your library.

What's in it:

- UPnP AV and OpenHome, using the renderer's own queue and Radio service where supported
- Native DSD up to DSD512 out to the streamer, DoP fallback for DACs that need it, PCM to 32/768, gapless
- DSD played on the device itself when there's no streamer in the chain - that one meant writing a decimator from scratch, which was the hardest part of the whole project
- Internet radio that holds stations other apps stall on, loop, or refuse outright
- A dedicated Classical section: composer, work, conductor, orchestra, soloist, period, form - with movements stitched back into whole works in the right order
- Queue, playback position, volume, favorites, tags and settings mirrored across every device you own
- Offline downloads, synced lyrics, ratings, private listening stats
- No account anywhere. Sync runs through your own private iCloud, so I never see your library or your listening history.

Tested during beta with Rockna, Linn, Lumin, Esoteric, Weiss, Moon by SimAudio, Technics, iFi, WiiM and Eversolo.

Fourteen days free, no account needed to try it.

https://apps.apple.com/app/id6762601663

If you try it and something doesn't work with your gear, post it here. I'd genuinely rather hear about it than not, and I ship fixes every couple of weeks rather than every couple of quarters. I'll be around in this thread.

[simbun]

Have you considered offering a simplified version with a one-time purchase option (similar to BubbleUPnP on Android)? A few of my friends on iOS would be interested in a clean, reliable UPnP app like this, but they wouldn't pay a subscription.

[serento]

(24-08-2026 20:20)simbun Wrote:  Have you considered offering a simplified version with a one-time purchase option (similar to BubbleUPnP on Android)? A few of my friends on iOS would be interested in a clean, reliable UPnP app like this, but they wouldn't pay a subscription.

I haven't considered this option mainly because the development is ongoing and never stops. This development has to be financially sustained. I work 12 hours a day on Serento. Monday through Sunday. I'm sorry that I can't offer this solution. Besides the subscription, there is an in-app purchase in the app that gives lifetime access and its a one time purchase. But its 4 times the subscription price.

[Donuk]

I tried to install this app on both my iPad and my Mac PC (Tahoe). Both of these have demonstrably found access to my network.

Lumin and Linn apps work fine. Minimserver installed on my Melco. I could not get Serento to discover my Library. Also made Minimwatch go a strange reddish colour and stop working.

I must admit that I applaud your efforts, but personally I would not want to pay a recurring fee for this sort of app unless it demonstrably sounded better than Lumin driving my Linn streamer.. And I don't understand how it might.

Possibly all my ignorance

Donuk

[serento]

(24-08-2026 22:50)Donuk Wrote:  I tried to install this app on both my iPad and my Mac PC (Tahoe). Both of these have demonstrably found access to my network.

Lumin and Linn apps work fine. Minimserver installed on my Melco. I could not get Serento to discover my Library. Also made Minimwatch go a strange reddish colour and stop working.

I must admit that I applaud your efforts, but personally I would not want to pay a recurring fee for this sort of app unless it demonstrably sounded better than Lumin driving my Linn streamer.. And I don't understand how it might.

Possibly all my ignorance

Donuk

Maybe there is a special situation with your setup that I haven't covered while discovering devices on the network. If you want to help, you can go into settings - logs - enable logs. Do a scan for devices and then go back to settings - logs - send logs. I will receive a file with what happened while scanning and I can solve the problem based on that.

Regarding sound quality, all my 30 beta testers have said it sounds better than anything on the market, but I will leave that to you to evaluate.

Thanks.

[simbun]

(24-08-2026 22:54)serento Wrote:  Regarding sound quality, all my 30 beta testers have said it sounds better than anything on the market

But we know better don't we A streamer would have to be so badly designed for a polling action to impact sound quality.

While I'm not familiar with JPlay, it appears to be your primary competitor. What key differences distinguish your app from theirs?

Your app looks gorgeous. Wishing you every success.

[serento]

Well, this is a touchy subject. Not for me, but for my competition. Because I know what I wrote and what I wrote never touches the audio stream, never touches the files. It's just a server - streamer communication, as we all know.

But there is an audible difference in Serento's favor. I will not theorize as to why the other apps sound less good, because there's no way of knowing and it's not really nice to talk about the competition.

Serento's unique features are, in no particular order:

1. Instant sync across devices of playback, favorites, tags, bookmarks, listen later, history, searches, playlists and settings. I'm using my own developed mesh networking technology. Usually this requires a server that can sync these things to the client but I managed without a server. It was a pain to implement but it actually works.

2. DSD playback on the local device. If you are not using a streamer you can playback your DSD files on the phone/mac or use a usb DAC attached. Not a lot of other apps do this. It requires writing your own DSD decimator (the one that matches the bits from DSD to the bits from PCM). A decimator is really hard to make because its all math. Advanced math. And just one bit off and your audio signal is compromised. I've spent countless days trying to get this to work.

3. Turn any folder structure into a nested tag structure. Browsing folders is slow. The performance depends on how fast the server responds and that depends on the type of hard disk you have, the network speed, the cpu and so on. To fix this, Serento can read your folder organization and create a tag hierarchy just like in your folders. Navigating a tag hierarchy is instant and offers all the benefits of a modern organisation system (rename, move, delete, add to playlist and so on).

4. Every week Serento builds 6 smart playlists called My Mixes, based on your listening history. All of them are based on different genres. The mixes are built using a pretty advanced algorithm, that will probably get better and better with time.

5. Serento comes with 75 preset radio stations that are hand picked by me. All FLAC, all tested for content and stream stability. All the beautiful cover arts are made by me. This list will grow in time. There are plans to include a radio directory in the future.

6. You can download any music from the server on your local device and take it with you.

7. You can start playing on your iPhone and pickup where you left off on your iPad. Everything is synced. The play queue, the play mode (shuffle, repeat), the scrub bar position, the track itself and so on. It's instant.

8. If you are not happy with the automatic album identification you can do it individually for each album. Just tap Identify and you will be presented with versions. Choose one and it will sync across devices. You don't have to do it on every device you own.

9. Sync schedule. You can have your iPhone or iPad do a nightly sync with your server so you have everything fresh in the morning. Just schedule a sync and let the background service do its thing. This requires that the device is with the screen off, charging and not doing any work like playing audio.

10. The Classical Music section is simply the best in the industry. I spent many days designing and figuring out what classical music listeners want and I received amazing feedback on the implementation. Not only it is beautiful but it serves the needs of the avid classical music consumer.

Everything else is what you expect from an app at this level.
More on features can be read here: https://serento.app/Home/Features

[simoncn]

I don't see a price on the App Store page or on your website. What is the annual cost?

[serento]

(25-08-2026 20:08)simoncn Wrote:  I don't see a price on the App Store page or on your website. What is the annual cost?

Annual subscription is $50.
Lifetime subscription is $200.

You can see the prices in the In App Purchase section of the app store page.

[simbun]

(25-08-2026 07:45)serento Wrote:  Well, this is a touchy subject. Not for me, but for my competition. Because I know what I wrote and what I wrote never touches the audio stream, never touches the files. It's just a server - streamer communication, as we all know.

Yes, just how a standard UPnP control point works (it just hands the URL of the track to the renderer). It's trivial to verify that the source is untouched by checking AVTransport.GetMediaInfo.CurrentURI

(25-08-2026 07:45)serento Wrote:  But there is an audible difference in Serento's favor. I will not theorize as to why the other apps sound less good, because there's no way of knowing and it's not really nice to talk about the competition.

If the source is untouched then there is no sound difference between control points, but there's no need to theorise given it's trivial to view the communication between the two devices. If I want to get a feel for how a control point works I'll normally play to a software renderer and enable logging, but it's simple enough to run a network capture to record calls and timings - which is only really relevant for polling/state change e.g. GetPositionInfo, GetVolume, GetTransportInfo.

It's ridiculous to claim that a control point can improve sound quality (when playing the same source), but if you don't, there will be a dozen apps that do so I guess it's just par for the course for "audiophile" products.