There are many different online tools out there, many are a waste of time. I have found GoodReads.com to be a a great use of my time.
When I first started, and arguably to this day, I used GoodReads somewhat sparingly and lazily. But, the more I use it, the more I benefit from it. Since I started using Good Reads, I have added 80 books to my list, 43 I have actually read and 7 I am currently reading.
I enjoy being able to see all of the books that I have read or listened to on audible.com. Back in the old days–about ten years ago, people would write their reading list in a journal or notebook to see what they have read. This is primarily all that I do on GoodReads.
I enjoy keeping a wish list. There are plenty of books out there and GoodReads has a vast data base on most of them. If you are interested in reading books, this is a great way to see what you may want to read next. It is also a way to see how other readers rates the books that you may be interested in reading.
Also, I like be able to monitor the progress of my reading. Sometimes, I get several reading projects going on at a time. Being able o see that I am, for instance, reading 7 books right now, maybe an indicator that I am trying to read too much at one time.
There are many other aspects of Good Reads that would be enjoyable, but all I have used it is to be a record of what I read and want to read, or have read. For these alone, this website is extremely powerful tool for me and my reading.