Put your calibre library in Dropbox or Google Drive. Get Calibre Cloud Pro to have a good-looking, easily searchable library on your device (you download from t

Put your calibre library in Dropbox or Google Drive. Get Calibre Cloud Pro to have a good-looking, easily searchable library on your device (you download from there as needed). Use Moon+ or some other reader to read the books. Calibre also has a server function (which Moon+ supports), but not everybody has a public IP to access their books everywhere. These are all Android, but there's probably some equivalent on iOS. You will want to convert all your ebooks to a format that your reader supports, such as epub. There are extensions for Calibre that will strip DRM if you're into that.