Libby is an app; the company that provides the books is called Overdrive. The libraries pay them for audiobook and ebook content for patrons to check out. If you like using the service, be sure to vote in favor if your library system has a millage issue on the ballot in a local election, because Overdrive service is expensive to purchase, and usage of it has skyrocketed since the pandemic. This year a lot of libraries I know have been forced to reduce the number of holds and titles that each patron can have at any given time, because they just can't afford to put any additional money into the service to cover increased popularity. (Tip about this: go ahead and check out anything that looks interesting on this platform, and just return it early if the first couple of chapters are not to your taste. Borrowing statistics are used to gauge how much library patrons want and use this service, and how much content to license, so if you want more money spent to give you a better selection, be a more active borrower and place a lot of holds. This is for Libby/Overdrive only. Also another tip: the advanced search function on the desktop Overdrive site is better than in the Libby app, so if you are trying to search by genre, etc. and not having good luck, try it on a computer rather than on a phone or tablet. Anything checked out while using a computer will still appear for reading/listening on your phone or tablet.)
Many libraries also offer the HooplaDigital service, which also offers music albums and video content in addition to ebooks and audiobooks. Hoopla has a different usage model than Overdrive, and is generally not quite as expensive because you can set the collection not to include really popular US titles. There is a lot of content on this platform that was published in Canada, the UK, Australia and New Zealand, and as Overdrive gets more popular and ends up with wait times fueled by demand, Hoopla's non-US authors are getting discovered by Americans. There is some really good stuff out there that Overdrive doesn't have, so if your library offers Hoopla, do give it a try. (One warning though; the selection on Hoopla is best in the morning. Their model does allow the Library to set a daily limit on the overall number of checkouts a system can allow in one day, and in many places lately, demand is causing that threshold to be hit by late afternoon, at which point nothing else may be borrowed by that Library's patrons until the system resets at midnight. For Hoopla, the library is charged a usage fee each time a title is checked out, rather than paying a flat collection fee based on what books are in the chosen selection, and patrons are subject to a total monthly borrowing limit, rather than the simultaneous borrowing limit that Overdrive has. So for Hoopla, best to only borrow things you really think you'll like. One other thing: while it is by no means the bulk of what is offered there, Hoopla includes a large selection of so-called "Christian Fiction", which is classed that way because the titles frequently include mentions of faith. A lot of readers also like using this particular limiter to search for romance fiction because there is also no explicit sex or profanity in those titles.

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