FOR PHONES ONLY
Do you get Voice Mails via e-mail or web access? Have you ever forgotten your headphones (or you do not even have any) and still wanted to listen to your Voice Mails with some privacy (e.g., being in the office or driving by bus)?
Voice Mail Player automatically plays audio and video files (audio part only) via your Android phone's ear-piece - like as you would take a phone call.
Voice Mail Player does not(!) include a file picker. It can be started like Android's default media player from any application that deals with media files. It's in the shared apps list. It can be used via gallery, e-mail clients, file pickers, download folder etc.
ATTENTION: It does not work on every phone, you have to try it first. This is because there is no real standard way of accomplishing this. Although it might seem to be taken for granted...
ATTENTION: This app uses the default Android media player under the hood. Hence, files which cannot be played by the media player cannot be played by this app.
For Android 4.3++ it needs now the permission READ_EXTERNAL_STORAGE.
This app will not work on devices without ear-pieces (obviously).
Take a look at the settings to configure Voice Mail Player's behavior for your needs. Of course, you can use your phone's volume control keys as usual.
Another attempt to fix problems under Android Lollipop. (It is confirmed that Google changed something in Lollipop regarding the earpiece that forbids easy usage, still investigating for you.)