You can use MiiTel Phone Mobile to play your voicemail and check your messages.
It's available for both iOS and Android.
How to play a voicemail
.
1 Tap [History] at the bottom of the screen
.2 Tap [Voicemail] to show only voicemail history
.3 Tap the voicemail history you want to play
.4 Tap [Play Voicemail]
.5 When the message "It's playing" appears at the bottom of the screen, the voicemail will be played
.The voicemail voice will be heard through your smartphone's speaker.