I live in Brooklyn and I love the public library system. Which is better to use, to read an ebook on my iphone? SimplyE or Overdrive?

I live in Brooklyn and I love the public library system. Which is better to use, to read an ebook on my iphone? SimplyE or Overdrive? - 1

That's up to you!

You don't have to just pick one. You can use whichever one has the book you want to read. Some libraries have added Hoopla to their mix. And some libraries have an app called Total Boox.
I use overdrive to download kindle books which I read on my kindle.