kai:
Thank you for asking this question in the support community! At the time of this post, ADTRAN does not have a VPN client for Android or Apple. However, here is a related post on VPN clients that can be used with Apple devices: https://supportforums.adtran.com/message/2983#2983
Please, let me know if you have any additional questions. I will be happy to help in any way I can.
Levi