Video Maker, Video Editor is the best app for you now which is totally free, supports creating videos from multiple photos, editing one or more videos with many unique and beautiful video effects. You can cut video, select the best part of video you want. In addition, the application also supports video merging, which will let you join multiple videos together.
Demo: https://codecanyon.net/item/video-maker-editor-photo-slideshow-allinone/35193557
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