Setting up a VPN on your Android or iPhone device is just as easy as setting it up on your computer. To begin, you'll want to download the configuration files from the synology server, or if you've already done that, you can use the same ones you installed on your computer for your phone.
To set up the android, you'll want to navigate to the Android Play store and either download this version if you have a newer device (4.0 and higher) or this version for older devices (1.5 and up). It's very possible that if you are installing the older version (and possibly the newer, I'm not sure), that you'll have to install TUN.ko Installer. TUN helps establish the virtual point-to-point IP link. If you have this problem you'll be notified like shown on the picture to the left and it will likely even open another page of details (like the picture below) giving you a link to install it. If it is installed, then you'll just open the program and load the drivers and all will be well again. This does happen to me every now and then because the drivers aren't loaded.
However, before you run into those problems, you'll need to connect your device to your computer and transfer your ca.crt and your openvpn.ovpn into the necessary folders. For me, it was under the /mnt/sdcard/Openvpn folder. From there you can start up the vpn client and you should be good to go now that you know how to trouble shoot any potential problem.
Now that you're connected you can check out the data transfers in the status bar of the phone. :-)
Currently the official OpenVPN (1.0.1 build 88) software is too buggy for it to be easily compatible with iOS 6.1.3 (10B329). When I attempted, I ran into many errors. The files worked on my desktop OVPN connection, however they failed when trying to work with the iPhone version. If/when the next release of OpenVPN is out there, I believe they will be fixing many of these issues and I will attempt an easy guide at that point. However, currently you would need to log into the server, run several commands modifying several files and start and stop some services then play with it on the iPhone as well, all far too dependent upon what version of Synology/openVPN you are running and iOS version. No elegant solution is possible currently. Sorry guys! :-(
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