There is a specific disappointment piano learners keep living through, and it has two shapes.
Shape one: you buy a practice app outright, it works, you like it, and then the updates quietly stop. The app still runs, the website still sells it, but nothing has shipped in years. As we write this in September 2026, the news archive on the site of Synthesia, the best-known one-time-purchase piano trainer, lists version 10.9, released in December 2022, as its newest release. To be exact about it: the Android build did get an update in February 2025, and the desktop app, which is what the news archive tracks, has stayed on 10.9.
Shape two: the app is alive, but you rent it. Thirty seconds of arithmetic on the popular subscription apps is sobering: the well-known names run from about 45 dollars a year for a single-purpose trainer to 130 dollars a year and up for the big teaching apps. Stop paying and, on most of them, access ends with the payments. Some of them are asked so often for a lifetime option that their help pages carry a canned answer explaining there is none. And apps die too: Read Ahead, a dedicated sight-reading trainer that serious teachers recommended, is no longer listed on the App Store.
Both shapes are the same bet from your side of the counter: you're hoping the developer's incentives stay pointed at you. With an abandoned one-time app, the incentive ended at your purchase. With a subscription, the incentive is pointed at your not-cancelling, which is related to your improvement but isn't the same thing.
The bet we're asking you to make instead
MidiSlayer is one payment. Buy it, keep it, it's yours to keep. Every update within the major version is included. There's a real free version, not a trial with a clock, so you can practise with it for weeks before deciding we deserve the money.
The obvious question is the honest one: what stops us becoming shape one? What stops the updates quietly stopping?
Nothing but track record, so here's ours, in a form you can check. MidiSlayer launched into Early Access on 31 August 2026. In the first twenty-four hours we shipped three releases, because early users found two real bugs and we fixed them the same day, and the app told you about both fixes itself, in its own changelog, delivered by its own updater.
That cadence is the product. Early Access means the app is finished enough to practise with every day and unfinished enough that what you report shapes what ships next, and the changelog is the receipt.
Worth saying, too: a one-time price isn't charity economics. The best-loved tools in this niche ran for decades on exactly this model. It works when the developer keeps earning new customers, and you keep earning new customers by shipping. That's the incentive alignment we wanted, and it's the whole reason we picked it.
The model doesn't merely permit active development, it requires it.
What the money buys, concretely
One payment gets every mode: nine of them, from note flashcards through graded sight-reading built on the ABRSM parameters, to full score play-through with real-time feedback from your MIDI keyboard, plus the arcade wing for the days when discipline needs a costume. A 69-piece public-domain score library, from Twinkle Twinkle to the Goldberg Variations, every edition credited.
Your key activates on two of your machines, the app works offline, and your practice data lives on your device, not on our servers, because analytics about your playing are for you, not for us.
Less than three months of the big apps' monthly plans, and the meter never starts.
If you're searching for a Synthesia alternative
The short version: MidiSlayer is the same buy-once idea, currently in active development, with a real free version so you can check it does what you need before paying. Synthesia is buy-once too, and cheaper, so the honest difference is what each one is for: falling notes with optional notation there, real notation with a MIDI keyboard listening and a graded sight-reading course here. We put the apps side by side, with sources.
If you have a drawer with an abandoned practice app in it, or a cancelled subscription that took your streak history with it, we built this for the person who opened that drawer. Try the free version for as long as you like. When it earns the purchase, it's one purchase.
The facts about other products in this post were checked against their sites and the app stores on 1 September 2026 and again on 3 September 2026. If something has changed since, tell us and we will correct this page.