For the most part, whether a book has DRM is a per-publisher decision, not per-storefront. e.g. TOR books are DRM-free everywhere (including Apple). That said,

For the most part, whether a book has DRM is a per-publisher decision, not per-storefront. e.g. TOR books are DRM-free everywhere (including Apple). That said, ebooks.com is great! Clean interface, easy to download old purchases, etc. It's my go-to for O'Reilly content.