Terms of use

Effective 12 September 2026.

Greatbook is published under the name Doublespaced by Justin Delano, an individual developer. Doublespaced is a trading name rather than an incorporated company, so "the developer" below means that person. Using the app means accepting what is written here.

What you may do with it

Use Greatbook for your teaching, on as many of your own devices as you like, for as long as you like. Show it to colleagues. The free version needs no key, has no seat count, and does not expire.

There are no plans to move features that are free today behind the key.

The premium version

Google Drive backup is the one paid feature. It is a single payment for a license that does not expire. There is no subscription.

The payment is taken by Polar, who are the merchant of record for the sale. Polar's terms govern the payment itself; these terms govern your use of the software.

You receive a key by email. A key may be activated on up to five devices, and a device can be released again from Settings to free the slot. The key is tied to the Google account you sign in with, and is for your own use rather than for sharing or resale.

The app checks the key occasionally, which needs an internet connection now and then. If it cannot reach the shop for a long stretch, Drive backup pauses until it can check again. Nothing has to be bought again, and no other part of the app is affected.

A key may be revoked if it was obtained fraudulently or if the payment for it is reversed.

Anything added to the premium version later is included at no further charge. If the premium version is ever discontinued, keys already sold keep working for the versions they were sold for.

Refunds

If it does not do what this site says it does, write to support@doublespaced.app within 30 days of buying and you will be refunded. You do not have to justify it, and the free version is unaffected either way.

Where the consumer law where you live gives you a longer or stronger right than this, that law applies and nothing here reduces it.

One thing is worth checking before asking: if Drive never appeared at all, your school may have blocked third-party apps for school Google accounts, which the Google Drive page describes. That is fixable at the school's end and is usually quicker than a refund.

What you may not do

Do not present Greatbook as your own work or your own product. Do not sell it, or sell access to it. Do not use it to break the law, or to break the rules your school or district has set for handling student information.

Your gradebook is your responsibility

Greatbook stores your work on your own devices and in places you choose. Nothing is stored for you anywhere else, and no copy exists that the developer could recover on your behalf.

So keeping your own backups matters here more than it would with a service that stores a copy for you. The app takes dated backups for you and asks you where to put them, and the page about your data explains how. If you lose the device and have no backup, the gradebook is gone, and the developer has no copy to restore from.

You are also responsible for the student information you enter, and for meeting whatever obligations your school, district, or jurisdiction places on you for handling it.

Greatbook is not the official record

Whatever your school uses as its student information system is the record of a student's grades. Greatbook is a tool for doing the work of grading. Grades that must be reported officially should be entered wherever your school requires them.

No warranty

Greatbook is provided "as is" and "as available", with no warranty of any kind, express or implied, including any implied warranty of merchantability or fitness for a particular purpose.

In plainer words: it is not promised to be free of defects, to be available, to be fit for any particular purpose, or to calculate any grade correctly. Check anything that matters before you act on it.

Limitation of liability

To the fullest extent the law allows, the developer is not liable for any loss arising from the use of Greatbook. That includes lost work, lost data, lost time, and any consequence of a grade that turned out to be wrong.

Where the premium version has been paid for, any liability for it is limited to refunding what was paid, and the refund section above says how to ask. Nothing here limits liability that the law does not allow to be limited.

The unsigned installers

The Windows and macOS installers are not code-signed, so both systems will warn you the first time you run one. Installing describes how to get past that.

Getting past that warning is your decision, and the risk of doing so is yours. Only download Greatbook from this site, and check that the download came from github.com/doublespacedapp/greatbook.

Ending it

Stop using the app whenever you like. Uninstalling it, or clearing the site data for the web app, is the whole of it. Your gradebook file and your backups are yours and are left alone; delete them yourself if you want them gone.

The developer may stop publishing Greatbook at some point. If that happens, what is already installed will not stop working because publishing stopped, and your gradebook files stay readable — they are plain files, and any program that reads that format can open them.

Changes to these terms

If these terms change, the effective date at the top changes with them, and the previous versions remain readable in the history of this page.

Getting in touch

Anything about a purchase, a key or a refund: support@doublespaced.app.

Anything about the app itself is better on the issue tracker, where other teachers can see the answer too. Please do not include real student names or scores in an issue, since issues are public.