The time travel doesn't make any sense. When did he build the Nixie tube device? How can he keep time leaping in times when Kurisu hasn't finished the device? In one time Daru creates the badges and in another it's Okarin.
Why do they all remember times that have been erased? How could he forget who gave him his first kiss.
Too many plot holes and becomes more about romance and feelings than science in the end. Great show though, easily 9/10.
Future Okabe built the Nixie Tubes, Suzuha brought them back.
He can't leap if Kurisu hasn't finished the device? If you can point out an instance where this happened, then I'd be willing to take this one seriously.
This one makes sense, since Okabe is the one leaping through time. They only made the badges in one of the timelines to comfort Suzuha, which Okabe got rid of. This is the only one that I don't feel so strongly about. Maybe this one's legit. I haven't read the VN in a few months though, so.
They remember things because everyone has Reading Steiner, Okabe's is just really strong.
The movie isn't canon.