Legal Terms of Use
Terms of Use
These are the rules for using Heavy Duty, the iPhone app for making invoices and estimates. Plain words, no tricks. Read them before you start billing with it.
The agreement
This document is an agreement between you and the team that makes Heavy Duty ("we", "us"). It covers the Heavy Duty app for iPhone and anything that comes with it, including the PDF templates and this website.
By downloading, installing or using the app, you accept these terms. If you do not accept them, do not use the app. If you have already installed it, delete it.
If you use the app on behalf of a business, you confirm that you are allowed to accept these terms for that business, and "you" means both you and the business.
You must be old enough to enter into a contract where you live. Nothing in these terms takes away any rights that consumer law where you live gives you and does not allow you to give up.
Your licence to use the app
We give you a personal, non-exclusive, non-transferable licence to install and use Heavy Duty on Apple devices that you own or control, for your own personal use or for the business you run. The licence lasts as long as you keep to these terms.
You do not buy the app itself. You get permission to use it. We keep everything we have not clearly given you here.
Under this licence, you may not:
- Sell, rent, lease, sublicense or otherwise pass the app on to someone else.
- Copy the app, except for the normal copy the App Store makes when you install it.
- Reverse engineer, decompile or take the app apart, except where the law says you may.
- Remove or change any copyright or ownership notices in the app or in the documents it produces.
- Use the app to build a competing product, or run it as a service for other people to bill through.
Your use of the app is also subject to Apple's App Store Terms of Service, including the Licensed Application End User License Agreement. Where those rules and these terms disagree about the App Store itself, Apple's rules apply.
A tool, not advice
Heavy Duty is a tool for producing documents. It lays out invoices and estimates, adds up lines, applies the tax rates and discounts you enter, and renders a PDF. That is the whole job it does.
It is not an accounting package. It does not do bookkeeping, it does not keep a ledger for you, it does not file or submit anything to a tax authority, and it does not sync with any accounting service.
Nothing in the app or on this website is accounting, tax or legal advice. Default wording, sample terms and conditions, tax fields, currency options and templates are starting points, not professional guidance. They are not checked against the invoicing rules of any particular country, state or trade.
If you need to know what a legal invoice looks like where you work, what tax to charge, or what you must keep and for how long, ask an accountant or a lawyer who knows your situation.
In short
The app does the arithmetic and the layout. You are responsible for the accuracy and the legality of every document you issue — the figures, the tax, the wording and the record keeping.
The documents you issue
Everything you type into the app is yours: your business details, your clients, your prices, your notes and your terms. We do not claim any ownership of it, and it stays on your device.
You are responsible for what you put in and what you send out. That includes:
- Checking the totals, the tax, the discounts, the markup and the currency before you send a document. The app calculates from what you enter, so a wrong rate produces a wrong total.
- Making sure each invoice contains whatever your local rules require it to contain, and that your numbering meets those rules.
- Having the right to use any logo, name or image you add to a document.
- Having the right to hold your clients' contact details and addresses, and handling them properly.
- Keeping your own records for as long as the law requires.
An invoice made with this app carries no approval from us. We are not a party to the deal between you and your client, and we take no part in whether you get paid.
Payments and subscriptions
Heavy Duty is free to start. Some features are part of an optional paid upgrade, which you can buy inside the app.
All payments are handled by Apple, not by us. We never see your card, and we do not process or store any payment details.
- ChargingPurchases and subscriptions are charged to the Apple Account you are signed in to on the device.
- RenewalA subscription renews automatically at the end of each period unless you turn renewal off beforehand. Apple charges the account when it renews.
- CancellingYou manage and cancel a subscription in your Apple Account settings on the device, under Subscriptions. Deleting the app does not cancel it.
- RefundsRefunds are decided by Apple under its own policy. Ask Apple, not us — we cannot issue a refund for an App Store purchase.
- RestoringIf you reinstall the app or move to a new device, use the restore option in the app to bring back a purchase made with the same Apple Account.
Prices and what is included in the paid upgrade can change. Any change to a subscription price is handled through the App Store, and Apple will tell you before it takes effect so you can decide whether to keep it.
If a paid feature stops being offered, that does not entitle you to a refund of an earlier period you have already used.
Acceptable use
Use the app for honest billing. Do not use it to:
- Produce false, fraudulent or misleading documents, including invoices for work that was never done or for a business that does not exist.
- Impersonate another business, or put someone else's name, logo or bank details on a document without their permission.
- Break any law that applies to you, or help someone else break one.
- Send unwanted bulk messages or email to people who have not asked to hear from you.
- Interfere with the app, get around a paid feature, or try to reach parts of it you have not paid for.
- Do anything that puts the security or the good name of the app at risk.
Because the app runs on your device and has no account behind it, we cannot see what you make with it and we do not monitor it. That does not make any of the above acceptable. If we learn that someone is using the app this way, we may end their licence.
Who owns what
The app, its code, its name, its icon, its design and its screen layouts belong to us or to whoever licensed them to us. So do the PDF template designs — Clean, Classic, Modern, Bold, Elegant, Techy, Simple, Trendy, Dynamic, Executive and Minimal — and the sample wording and default labels that ship with them.
You may use the templates to produce and send your own business documents, with your own logo, colour and labels, for as long as your licence lasts. That is what they are for.
You may not extract, redistribute, resell or republish the template designs themselves, or offer them as templates in another product, whether or not you changed them first.
Your content stays yours. Adding your logo to a document does not give us any right to it beyond letting the app place it on the page on your device.
Your data and your backups
Heavy Duty works offline and has no account. Your invoices, estimates, clients, catalog items, payments and settings are stored on your iPhone. We do not run a server that holds them, so we hold no copy of them and cannot recover them for you.
Backups are your responsibility. If the device is lost, broken, wiped or reset, or if you delete the app, the data in it goes with it.
The app gives you two ways to take your data out:
- A full JSON backup of everything in the app.
- A CSV file you can import into QuickBooks.
Export regularly and keep the file somewhere safe, the same way you would keep any other business record. Also keep whatever device backup you normally use.
How the app handles information is described in the Privacy Policy.
Other people's services
When you send a document by email, WhatsApp, Messages or the iOS share sheet, or when you print it, the document is handed to that app or service and leaves ours. What happens to it after that is governed by the terms and privacy policy of whoever runs it.
We do not control those services and we are not responsible for them, for whether a message arrives, or for what they do with the file. The same goes for the App Store and for map data used to show a client's pin.
No warranties
The app is provided as it is, with whatever features it has today. We do our best to make it correct and reliable, but we do not promise that:
- It will be free of bugs or will never stop working.
- Every calculation, template or default setting suits your trade, your country or your tax rules.
- A document it produces will satisfy any particular authority or client.
- It will keep working on future versions of iOS or on every device.
- Data on your device will survive a fault, an iOS update or an app update.
To the extent the law allows, we exclude all warranties that are not written down here, including any implied warranty of merchantability, fitness for a particular purpose or non-infringement. Some places do not allow that exclusion, and in those places this section applies only as far as it is allowed.
Limits on liability
Put plainly: this is an inexpensive app that draws documents on a phone. It cannot carry the risk of your whole business.
To the extent the law allows, we are not liable for lost profit, lost revenue, lost or corrupted data, an invoice that went out wrong, a payment that never arrived, a fine or penalty, or any indirect or consequential loss arising from your use of the app or your inability to use it.
Where we are liable despite the above, our total liability for all claims is limited to the amount you actually paid for the app in the twelve months before the claim. If you never paid anything, that amount is nil.
We do not exclude liability for anything that cannot legally be excluded, such as fraud or death or personal injury caused by our negligence.
Apple is not responsible for the app or for its content. Apple has no obligation to provide support or maintenance for it, and any claim about the app is between you and us, not Apple.
Ending this agreement
You can end it at any time by deleting the app from your device. If you have a subscription, cancel it separately in your Apple Account settings, because deleting the app does not stop the renewal.
Your licence ends automatically if you break these terms. We may also stop offering the app, or stop supporting an older version of it, at any time.
When the licence ends you must stop using the app and delete it. Export your data before you do — once the app is gone from the device, the data in it is gone too, and we have no copy.
The sections on intellectual property, warranties, liability and these general points continue to apply after the agreement ends.
Changes to these terms
We may update these terms as the app changes. The current version always lives at getheavyduty.com/terms, and the date at the top tells you when it last changed.
If a change matters — if it affects your rights or what you pay — we will make that clear in the app or on this page before it takes effect. Using the app after a change means you accept the updated terms. If you do not accept them, stop using the app and delete it.
If any part of these terms turns out to be unenforceable, the rest still stands.
Contact
Questions about these terms, or about the app, go to support@getheavyduty.com. A real person reads it. Tell us your iOS version and what you were doing when something went wrong, and we will get further, faster.
For billing, refunds and subscription changes, contact Apple through the App Store — those are handled on Apple's side and we cannot change them for you.
That is the whole agreement.
No account, no cloud, no small print about what we do with your client list. Download the app and send the first invoice.
Free to start, with an optional paid upgrade. iPhone, iOS 26.