Life is a personal record-keeping application. It keeps one person's day in one place — where their time went, what they planned, what they spent, what they ate, what they are reading, and the notes they keep alongside all of it.
It is a private project, not a commercial product. Accounts are created by invitation only and there is no public sign-up. Everything in it belongs to the person who entered it.
A signed-in account may optionally connect Google Calendar and Google Tasks. When connected, Life reads that account's calendar events and due tasks and displays them alongside the person's own tracked time, so a day reads as one picture rather than two. Events and tasks are fetched when the calendar is opened and are not copied into the database — the only exceptions are the credential needed to keep the connection alive, and any event the person deliberately converts into one of their own entries.
Connecting is entirely optional and the application works without it. It can be disconnected at any time from Settings, or revoked directly from your Google account. The Privacy Policy sets out exactly which permissions are requested and why.