In short
Sticky Widget is a free, open-source program. You may use it for anything you like. It comes with no guarantees, and you can stop using it at any time by uninstalling it and revoking its access to your Google account.
The licence
The app is provided free of charge. Its source code is public at github.com/joginfrancis/google-tasks-sticky-widget and may be read, modified and redistributed under the terms of the licence published there.
Your Google account
The app acts on your Google Tasks data on your behalf and only while you have connected it. What it does with that data is described in the privacy policy, which forms part of these terms.
Your relationship with Google is governed by Google's own terms, not by these. This app is independent and is not affiliated with or endorsed by Google.
No warranty
The app is provided “as is”, without warranty of any kind, express or implied. It may contain faults. It may stop working if Google changes its service. To the fullest extent permitted by law, the developer is not liable for any loss or damage arising from using it, including lost or altered task data.
Your tasks live in Google Tasks, not in this app, and deleting a task here deletes it there. Undo is offered for a short time after a deletion; once it is gone, it is gone. Treat the app as a window onto your tasks, not as a backup of them.
Acceptable use
Use the app only with accounts you are entitled to use, and only in ways permitted by Google's terms and by the law where you live. Do not use it to access anyone else's data without their permission.
Ending it
You may stop at any time: uninstall the app, and revoke its access at myaccount.google.com/permissions. Nothing of yours is kept anywhere but your own computer and your Google account.
Changes
These terms may change; the current version is always on this page with its date. Continuing to use the app after a change means accepting it.
Contact
Questions: open an issue on GitHub.