Whenever I get a new iPhone, I always like to start brand new as a way of pruning what I need. Ever since I received the iPhone 5, I held back on installing Due because I wasn't convinced that it offered the same amount of benefits in turn with the amount of effort that I would put in.
However, Sven Fechner has posted a link to a Keyboard Maestro Macro that allows a quick entry from the desktop version of OmniFocus to the desktop version of Due.
This might be the macro that puts Due back on my phone.