Will I be charged during the trial? Do I need to cancel it?
No card details are collected and no payment is taken during the trial, and a paid subscription doesn't start automatically when the trial ends; you don't need to cancel.
No. No card details are collected and no payment is taken during the trial. On the payment screen in setup, the card fields are disabled and the amount due today shows as $0. The monthly amount and date on that screen are for information only; a paid subscription doesn't start automatically when the trial ends.
A paid subscription doesn't start automatically when the trial ends, so you don't need to cancel the trial. While the trial is running, the cancellation card on the Settings › Subscription and billing page also says “No need to cancel during the trial.”
If you don't want to continue, you don't need to do anything. Shortly after the trial ends, scans stop and your data stays visible in the dashboard.