I can also recommend that.

For the legal stuff, Calibre with the DRM removal plugin has been great. Because I hate DRM, I mostly bought physical copies, which obviously need space, but Calibre has solved that issue. I can buy digital copies with Kobo so I still support the author, but is cheaper than physical and don't need physical space, and I can remove the DRM and convert to a different file type so I can use the reader app I want. This has been especially great for manga, as Kobo's app sucks for that.