First, make sure you enable DLNA media streaming from the dashboard settings (under Media). I have not tried streaming to my iPad in a while…I did use VLC for iOS a while ago (free software - http://www.videolan.org/vlc/download-ios.html ) and was able to watch movies on my iPad smoothly for some movies that had lower bitrate. Other videos that had higher bitrates stuttered a lot making them unwatchable. So to be able to enjoy a smooth playback over wi-fi you will need to have movies that have been compressed a bit using a tool like handbrake (or were already compressed when you got them, as it is all reliant on network bandwidth. Also, a quick Google search led me to this link - I have had no personal experience with any of the apps on this page so YMMV → http://appadvice.com/appguides/show/dlna-streaming
One very important thing - DLNA works only within the network that the EX2 is in. It won’t work from outside the network where the EX2 is kept. But VLC does support streaming via ftp - so if you do want to watch a movie from outside the network, you ca try that. But again YMMV as it is reliant on the network quality of both the connections - the one at the iPad end and the one at the NAS server end (not the gigabit LAN speed - but the WAN connection quality esp. the upload speed is important).
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