iTunes Match works fine (most of the time), but what if you already have a large collection of audio content in Dropbox or Google Drive? CloudBeats allows you to turn your Dropbox, Google Drive, Box, MediaFire or OneDrive account into an iOS music player.
CloudBeats solved a very specific problem for me. I wanted a way to download audiobooks (.m4b files) from Dropbox to my iPhone without having to sync through iTunes. CloudBeats not only allows me to do this, but also adds other power user features like bookmarks and variable playback speed. It also allows you to sync specific folders in order to save your data allowance.
CloudBeats would also work well for those random audio files that you download that you end up sending to Huff Duffer from a Dropbox link.
Get CloudBeats on the App Store for $4.99.