Finding the right beta readers alone can be challenging for an author, and trust can always be an issue. I have both used https://betareader.io/ and https://betabooks.co/ while polishing my novel, and I’m happy to share my experience.
With these two beautiful apps, you can be in control of your content, and who is reading it, since you are the one inviting betas of your choice.
You can track the process and make changes to your manuscript as you go if you enable the comments for your guests.
Easy to use, with excellent tools and a friendly interface that does not require much knowledge to navigate. Plans start free, but there is different pricing to unlock more features. You can also email customer support to help you, or if you have any questions, and they will get back to you in a short time —a great solution for writers.