Review based on Movie alone, didn’t even know there was a manga.

LIKES:
Yuki great in every role he acts
Sensible girl, even if she’s clumsy. Very mature compared to everyone else in this movie.
Handsome lead but not overly hyped up by the writers for once.
Cinematography and colour pallet was good too.
Loved the fireworks.
Music choice was okay and fit the scenes.
Acting was good overall.
End was satisfactory.

DISLIKES:
WRITING
A few hugs and hand holding, but disappointed there was no kisses made by the ML, by high school couples do that.
Ren & Ninako didn’t have any noticeable growth, the characters that had growth were Takumi and Mao.
Ren came across as a bit boring and stiff. Also when the change came for his love interest, it wasn’t very impactful, because he had little time to notice the girl or had limited “special” moments that came across as romantic. Those moments shown in the flashbacks were more ‘let’s be friends’ than ‘I love you’.
MUSIC lyrics were appropriate, but sometimes it was too loud, so the actor/actress voices were over powered
PRODUCTION
Back lighting (the sun/bright day) made seeing their faces sometimes hard because it was too bright
too many flash backs, so it felt like time filler.
Pacing was a little slow in areas. Too much time spent on running around and multiple flashbacks, when only two each would have been enough.
ACTING
No chemistry between Sota and Arisa.

OVERALL: Fast, easy watch, hardly any drama. Watch it if you are a fan of Yuki (Yamada).