I'm trying to switch my app from Rails 3.2.13 to Rails 4. In doing so, I've hit one main snag -- I use the gem mobile_fu in order to determine if users are coming from a mobile device. That gem requires railties 3.2.13, but rails 4.0.2 and sass-rails for rails 4.0.2 both require railties >= 4.0.
What's a good way to solve this problem? I'm happy to dig into the mobile_fu code as it doesn't seem particularly tricky, but I have very little experience dealing with railties and what dependencies on railties mean.
Thanks!