Last updated 15 September 2026
These terms cover the Arity desktop app and this website, both published by Mikademy. Buying a licence, or using the free trial, means agreeing to them.
Arity is made and supported by Mikademy. The sale itself is made by Creem (Armitage Labs OÜ, Estonia) as merchant of record: they take the payment, handle the tax, appear on your bank statement and issue your receipt. Support, updates and everything about the software are ours.
One payment of $29.99 buys a lifetime licence to Arity for the desktop. It does not expire, it includes every future update, and it may be used for personal, academic or commercial work alike.
A licence activates on up to 3 devices at a time. You can release a device in Settings → License and use the seat elsewhere whenever you like. The licence is yours personally or your organisation's - it is not for sharing with people outside it, and not for resale.
Two limits, and they are the ordinary ones:
The download is the complete app, unactivated. In that state it keeps three diagrams per folder and stamps the presentation window. It is offered so that you can decide before paying; it comes with no promise that it will stay available on the same terms.
The price is $29.99 in US dollars, once. Creem may add VAT, GST or sales tax according to where you are, and will show the total before you pay. We can change the price of new sales at any time; a licence already bought is unaffected.
Updates are free for the life of the licence and are delivered in the app. We do not promise a release schedule, a particular feature, or that a future version will run on an operating system that has itself stopped being supported.
You can have your money back for any reason within 14 days of buying: write to the address at the bottom of this page with the email you paid with, and Creem refunds to the original payment method, usually in five to ten business days. Your licence stops working when the refund is issued.
After that window we will still refund a purchase that does not work on a supported system and that we cannot fix. Purchases of Arity for iPad are refunded by Apple under App Store terms, not by us.
Diagrams you make with Arity belong to you entirely. We claim no licence over them, and since they never leave your machine, we could not act on one if we wanted to. Keeping them backed up is your side of that bargain.
The website, the download service and the licence service are run with care but without a guaranteed uptime. If the licence service is unreachable, an already-activated copy keeps working; if it were to disappear for good, your .arity files are plain JSON and remain readable without us.
Arity is provided as it is. It checks diagrams against the notation each mode carries, and it can be wrong: a validator finding no problem is not a professional opinion that a design is correct. To the extent the law allows, we disclaim the implied warranties of merchantability and fitness for a particular purpose.
Where liability can be limited by law, ours is limited to what you paid for the licence, and we are not liable for lost work, lost profit or indirect loss. Nothing here limits liability for death, personal injury or fraud, and nothing takes away a statutory consumer right you have where you live.
Break the terms above and the licence ends; we will say why first, and only for something that is not put right. You can stop using Arity at any time, and your files stay yours and readable either way.
These terms are governed by the laws of Vietnam, where the publisher is based, and a dispute that cannot be settled between us belongs to the competent courts of Vietnam - again without prejudice to consumer rights that apply where you live.
We may revise these terms; the date at the top says when we last did. A revision applies to what you do after it is published, never retroactively to a licence already bought.