1001 Pro Calculators and Tools
Support
Every calculation is worked out on your phone. There is no account and no sign-in. For help with the app, a purchase or a calculation, write to the address at the bottom of this page — requests are answered by email.
The Pro subscription
Pro is one auto-renewing annual subscription. It is £0.99 for the first year as an introductory price for a limited time, and £2.99 a year afterwards. It is sold by the store you installed the app from, not by this app, and your payment details never reach us.
To cancel or change it:
- On Android: Play Store → Payments & subscriptions → Subscriptions.
- On iPhone or iPad: Settings → your name → Subscriptions.
Access continues until the paid year ends. If you reinstall or change phones, use Restore purchase on the Get Pro screen in the app.
The 7-day free trial
The free trial is the store's own: seven days on the annual Pro subscription, started from the app and listed in your store account like any subscription. It opens all 1,001 calculators, the worksheets and every trade tool. Cancel before the seven days end and nothing is charged.
The Trade Tools
The Trade Tools are a single one-off purchase covering every trade. They are yours permanently, the purchase includes a year of Pro, and they are restored from the store on a reinstall or a new phone.
Calculations and advice
Results are arithmetic based on published formulas and the figures you enter, for general information and planning. They are not financial, tax, legal, medical, engineering or other professional advice, and they are not a final figure: check any result before relying on it, issuing it to a customer or using it for payroll, pricing or compliance. The full terms are in the privacy policy and terms of use.
Common questions
An answer looks wrong. Every calculator shows its working — open the worked steps and check which figure it took. If the working is right and the answer still disagrees with a published example, send both and it will be looked at against the source.
A calculator is locked. 250 calculators are free forever. The rest are part of Pro. A locked calculator still shows you what it does before you decide.
My saved work has gone. Everything is stored on the device and nowhere else. Uninstalling the app deletes it, and there is no server copy to restore from. Device backup — Google Drive or iCloud — may hold a copy if you had it switched on.
Rates and tax bands are out of date for my country. Tell us which calculator and which country, with a link to the body that sets the figure.
Copyright
1001 Pro Calculators and Tools, including its code, catalogue, categories, lists, written content, visual design, keypads, worksheets, trade tools and document templates, is the original work and property of One App Company. Copying or imitating any part of it without written permission infringes our rights. Mathematical formulas themselves are not claimed. The full notice is section 10 of the privacy policy and terms of use.
Contact
hello@oneappcompany.com
Please include your device, the app version, and the name of the calculator. The version is at the bottom of the app's Settings screen.