Project ManagementΒΆ
There are different ways that teams may choose to manage their project. If you're using something like gitlab/github then it probably makes sense to keep that project management tool as close to the code as possible (IE just use the built in issue ticketing system).
If you're working with people who are uncomfortable with those systems consider using something like Trello.
Ultimately this is up to your team, but you must have SOMETHING to keep track of tasks.
And no, a google doc TODO list is probably not enough.