I made the move from the Verizon Galaxy Nexus to the Maxx a few weeks ago so I had previously been using JB. When the Nexus made the upgrade from ICS to JB I did indeed lose Fox-fi. I also had WiFi Hotspot And USB Tether by SVTP installed and that app continued working. When I moved to the Maxx I had totally forgotten about Fox-fi and installed the SVTP app again. I assume that since the SVTP app kept working on the Nexus after JB that it will continue working on the Maxx. Time will tell the accuracy of my assumption. Fingers crossed.
By the way, although I took a bit of a step back by not having the latest version of android when I moved to a refurbed Maxx, I don't regret it. The battery life on the Maxx is outstanding and the OS on my Maxx is about to be on par with my Nexus. Glad I made the move.
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