We read every message and we answer. Ondaris is published by SCOPT Inc.
The quickest way to reach us is by email. Please include your device and iOS/Android version, and — if it is about a specific calculator — its name and the inputs you used, so we can reproduce it.
We aim to reply within two business days.
On the Home screen, tap the person icon at the top right to open Purchases and data, then tap Restore purchases. The same control is on the Ondaris Pro screen. Your Ondaris Pro unlock is tied to the Apple Account (or Google account) that bought it and will be restored at no charge. Make sure you are signed in to that same store account.
No. Ondaris Pro is a one-time, non-consumable purchase — there is no recurring charge and nothing to cancel. The free features stay free, and every formula page (the equation, variables, assumptions, validity range and source) is readable without any purchase.
Purchases are processed by Apple or Google, and refunds are handled under their policies, not by us. On iOS and iPadOS, request a refund at reportaproblem.apple.com. On Android, follow Google's refund request instructions for Google Play. If something in the app went wrong, please also email us so we can fix it.
Yes. Every calculation runs entirely on your device. The only time Ondaris uses the network is to fetch the Pro price and to verify or restore a purchase, and that carries nothing that identifies you.
None that identifies you. There is no account, no advertising and no analytics. Your projects, parameters and notes stay on your device. See the full privacy policy.
Open Settings and use "Delete all projects on this device". Deleting the app also removes everything it stored locally.
Ondaris deliberately refuses to report a quantity outside the range where its model is valid, rather than report it wrongly — so a blank result may be correct. Check the assumptions and validity range on that calculator's formula page. If you still believe a result is incorrect, email us the calculator name and your exact inputs and we will investigate; the correctness of the mathematics matters to us.
Set the answer you need and the required input follows — available on 62 of the 66 calculators. It is not offered on the Smith chart or the pyramidal horn, where the curve turns over so one target can have two valid answers, nor on the two single-step converters, where switching a unit already is the inverse.
Yes. A one-port Touchstone .s1p file from a vector network analyser can be dropped onto the Smith chart, so your measured sweep sits over the synthesised one. The file is read on your device and is not transmitted anywhere.
Any calculation can be exported as PDF, CSV, LaTeX, Python or MATLAB, carrying the assumptions, validity range and source clause with it. The file is created on your device and handed to the share sheet — you choose what happens next.
Yes. Every control is labelled, text scales with your system text-size setting, and charts carry a spoken summary rather than being drawn only. Ondaris has been tested with VoiceOver on iOS; TalkBack testing on Android is ongoing. If you hit an accessibility barrier, please tell us — we treat those as bugs.
Ondaris is a calculation and reference tool, not a simulator or a substitute for measurement, a licensed engineer's sign-off, or the standards themselves. See the terms of use for the full statement.
Ondaris