Last updated: September 1, 2026
These terms cover the use of the app “Kurbl: Indoor Cycling” and its paid features (“Kurbl+”). The provider of the app and your counterparty for its features is:
Michael Lopes Pinto
trading as: 3D Druck Michael Lopes Pinto (sole proprietorship)
Staufener Str. 26
79189 Bad Krozingen
Germany
Email: info@mlp3d.de
You buy Kurbl+ as a one-time purchase through the store you use (App Store: Apple Distribution International Ltd., Hollyhill Industrial Estate, Hollyhill, Cork, Ireland; Google Play: Google Ireland Limited, Gordon House, Barrow Street, Dublin 4, Ireland). Payment and invoicing run entirely through that store. What Kurbl+ actually gives you is owed by the provider named above.
Kurbl is a 2D cycling game. It reads performance data from a smart trainer, a power meter, or a cadence sensor over Bluetooth, turns it into movement along a route and, where your equipment supports it, controls the resistance.
Free permanently and without an account: connecting to your equipment and the full display of everything it reports, free riding with no time limit, holding a fixed watt or resistance value for as long as you like, the ramp test that establishes your reference power, importing your own routes from GPX files, and coins, levels, and the shop. Three of the fourteen included sessions and the first two sessions of the beginner course are free as well.
Kurbl+ unlocks, for a single payment, the features that unfold over time: the remaining included sessions and courses, writing and saving your own sessions, and your training history. Sessions you have written yourself stay rideable even if Kurbl+ is not, or is no longer, unlocked. What is included can differ between platforms. The connection layer is never put behind the purchase.
Kurbl needs no internet connection and no server of ours to run. We owe you no continuous availability of an online service, because there is no online service.
Kurbl is a game and a training tool, not a medical device. The app gives no medical, sports medicine, or therapeutic advice, makes no diagnosis, and does not monitor your health. The sessions, courses, and ramp test it includes are general suggestions based on widely used training patterns, not a plan built for you personally. Talk to a doctor before you start training, especially if you have a pre-existing condition, are pregnant, are returning after a long break from exercise, or are under 18.
While it runs, the app changes the resistance of your trainer, sometimes sharply and sometimes suddenly. Setting the equipment up safely and to the manufacturer’s instructions, judging what you can take, and deciding whether to start, continue, or stop a session are yours. The full guidance is on the Health and Safety page and forms part of these terms. Where our guidance conflicts with the safety and maintenance instructions of the manufacturer of your trainer or your bike, the manufacturer’s instructions take precedence.
Kurbl shows values it partly measures and partly calculates. Measured are the values your equipment sends. Calculated are speed, distance covered, elevation gained, and energy expenditure, among others. If you have nothing that measures watts, the app estimates your power from your cadence and from a figure you give it, or, in manual mode, works from the figure it sets for you. The app labels values like these as estimated.
Every value shown is a guide value for your training. None of them is intended for medical purposes, for competition, or for any purpose that depends on metrological accuracy. Your reference power from the ramp test is likewise an estimate following a widely used protocol, not a measurement in the technical sense.
Kurbl speaks the standard Bluetooth profiles Cycling Power Service, Fitness Machine Service, Heart Rate Service, and Cycling Speed and Cadence. We do not warrant that every individual device works fully. Older trainers in particular may implement these profiles only in part, and manufacturers can change how their devices behave with a firmware update at any time. That is why connecting and reading values are free permanently: you can check before you buy anything whether your equipment works properly with the app. We deliberately use no manufacturer-specific or undisclosed protocols, and for that reason we do not offer manufacturer-tied virtual shifting.
Kurbl is not affiliated with any manufacturer of training equipment or with any other training platform, and is neither endorsed nor reviewed by them. Brand and device names are used solely to describe compatibility. All trademarks belong to their respective owners.
You can import GPX files to ride a route of your own. That is on you: only load files you recorded yourself or hold the necessary rights to. Some map and route portals prohibit reuse of their data in their own terms. We do not check where a file came from and cannot check, because it never reaches our systems.
We do not warrant that every GPX file is usable. The app may reject files without elevation data, with corrupt points, or in a different format.
Kurbl+ is a one-time, non-consumable purchase, not a subscription. There are no recurring charges. The price that applies is the one your store shows you before you buy; it differs by country and currency.
Once you have bought Kurbl+, you can restore the unlock on your devices with “Restore purchases”, as long as you use the same store account. The App Store and Google Play are separate systems: a purchase in one does not unlock the app in the other.
Purchases, refunds, and any right of cancellation are governed by the terms of the store you bought from. We do not process refunds ourselves; the store does.
If you live in the EU, the EEA, or the United Kingdom. For digital content not supplied on a physical medium, your statutory right to cancel can end before the usual period runs out: it lapses once performance has begun with your prior express consent, you have acknowledged that you thereby lose the right to cancel, and the trader has given you confirmation of the contract. This follows Article 16(m) of Directive 2011/83/EU as implemented in the law of your country, and in the United Kingdom the Consumer Contracts (Information, Cancellation and Additional Charges) Regulations 2013. The trader in this case is the store, and the store runs this process.
If you live elsewhere. There is no statutory cooling-off period for a purchase like this. Whether you get a refund is decided by your store under its own refund policy.
Kurbl+ is digital content, and we owe you the updates needed to keep the app working as agreed for a reasonable period, in particular bug fixes and adjustments for new operating system versions. That does not give you a claim to new features. This is why we never advertise Kurbl+ as lasting “forever”. We say what is true instead: no subscription, no recurring charges.
If you live in the EU or the EEA, this obligation is also a statutory one, under Article 8(2) of Directive (EU) 2019/770 as implemented in the law of your country.
We are liable without limit for intent and gross negligence. We are liable without limit for death, personal injury, and damage to health caused by our negligence, and nothing in these terms limits or excludes that.
For ordinary negligence beyond those cases we are liable only where we breach an obligation that is essential to the contract, meaning one whose fulfillment makes proper performance possible in the first place and on which you may reasonably rely. In that case our liability is limited to the foreseeable damage typical for this kind of contract.
If you live in the EU, the EEA, or the United Kingdom. Liability under the German Product Liability Act, and any equivalent product liability regime in your country, is unaffected by the above.
Despite careful engineering, data loss cannot be ruled out entirely, for instance through device damage, mistakes in use, or uninstalling the app. Your data lives only on your device. On Android, Android Auto Backup saves it into your Google account; on iOS, your iPhone’s device backup does. Both are run by your operating system, not by us. So check for yourself that your device’s backup is switched on.
Where mandatory consumer protection law of the country you habitually live in gives you more than the above, that law prevails.
We grant you a simple, non-transferable right to use the app on the devices you use, for your own purposes. You may not reverse engineer or modify the app or circumvent its technical protection measures, except where the law expressly allows it. Your statutory rights, in particular those of any user of a computer program under applicable copyright law, are unaffected.
The coins you earn and the levels you reach in the app are a game element with no monetary value. They cannot be bought, transferred, or exchanged for money, and there is no claim that they survive a change of device or a reinstall.
These terms do not limit the mandatory rights you have as a consumer under the law of the country you habitually live in. Where these terms conflict with mandatory consumer protection law, that law prevails.
We may adjust these terms when the app, its features, or the law changes. The current version is always on this page.
German law applies. This choice of law does not deprive you of the protection given to you by mandatory consumer protection provisions of the country you habitually live in.
If you live in the EU or the EEA, this follows Article 6(2) of Regulation (EC) No 593/2008 (“Rome I”).
If any provision of these terms is invalid, the remaining provisions stay in force.
For purchases through the Apple App Store, Apple’s Licensed Application End User License Agreement applies in addition to these terms.