Nov 14, 2017. Using Synology DiskStation as a VPN server using built-in Android VPN client. battery juice on your phone/tablet, go for L2TP/IPSec instead; It is recommended to use OpenVPN if you can but since it imposes more load on the CPU and requires a 3rd party app on your phone I'm not covering it here. Sep 27, 2017  · Free Download OpenVPN 2.4.4-I601 – A full-featured SSL VPN solution which…