Hey, not sure if this will work for everyone. I'm packing a Casio Commando as my phone, because I am a klutz. And I needed a smartphone.
Unfortunately, the poor thing doesn't have enough 'oomph' to push GR Network. So, I had to get creative. Again I am not sure if this will work for everyone, and you will have to have a PC to do this on, but here goes.
1) Pick up 'BLUESTACKS' http://bluestacks.com/ android apps for PC program. CURRENTLY FREE, not sure if it will remain so. Install. (If you have an android phone, tether it to your bluestacks account.). Default it comes with Amazon and a couple others (NOT SURE IF THEY HAVE THE GOOD GR NET APP).
2) On your phone, install the BlueStacks sync app, and follow all instructions given by the program (and the emails sent).
3) Sync GR Net (Download it from Google Play, using the link provided by Ubi_Antoine in http://forums.ubi.com/announcement.php?f=366 ) to your Bluestacks account. After a while it will show up on your PC.
4) It will be a bit sluggish, and will take a minute, but once you get it right, it will work.
Not a very 'mobile' solution, but workable.