I believe the mobile version of adobe premiere rush is free on the app store. Used it for this when I was too lazy to bring out my cameras and too lazy to convert apples stupid .mov files to mp4.
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Definitely not my best work, but it was all made on an iPhone during a 24-hour car ride back from Targhee. As far as actual tips go, do something interesting and try to match it up to the music. I am by no means an eheath but you can make something interesting with pretty limited effects and knowledge.
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For this one, the vid within vid, some color grading to make the crappy camera quality look intentional and trying to match with the song went a long way.
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And finally, with this example, break up your video! We didn't have many clips for this one but even having somewhat of an Intro (broll):Clips:Crashes:Interlude(broll):Clips:Closing can go a long way for making a shitty incomplete edit like the above one look sorta finished and complete.