Any suggestions? As I wish to film, edit, and upload videos during Oxfam's 100km Trailwalk next year 

This thread from earlier this year is basically what I'm talking about (as I tried googing before posting this thread, but only found other people who are also looking like me):

Unfortunately the only two suggestions from there is one which has got heaps of awful reviews and another mediocre one which does it all in the cloud (which is useless for me, most of the time during the trailwalk I'll have no reception, only for short periods which I'll be using to upload it to YouTube. Not for editing! Should all be done on phone. As I've got an HTC One X it ought to be powerful enough for basic video editing).