When you're finished preparing tracks and playlists, you need to get them into your DJ app. Lexicon makes this easy. Open the Sync page, pick your target DJ app and press Sync. This copies your tracks and playlists into the selected application. You can choose to sync only certain playlists instead of the whole library. Lexicon keeps your playlists identical across apps.
If you play on different hardware, you may need to convert your library between Rekordbox, Serato, Traktor, VirtualDJ, Engine DJ or djay Pro. Lexicon handles this gracefully - it was designed to make sure your metadata (including cue points and playlists) is preserved when moving between apps. To import an existing library, go to Sync ➡ Import tracks & playlists, choose your source (e.g. Rekordbox 6/7) and start importing. Afterwards, you can export to another app in the same way. You can choose how to map hot cues to memory cues or vice versa when exporting to Rekordbox.