If you want a template-based app for quick creation of advanced transition cuts, Pixery is a good option. It's a collection of mobile apps for content creators, including Compose, a template app with advanced transition cuts and beat matching, good for creating video content on your phone that looks pro.
If you want a wider range of editing abilities, check out FlexClip. This free online video editor has more than 6,000 templates and a large library of assets, including 4 million+ videos and photos, 74,000+ music tracks and 200+ transitions. It's got advanced editing abilities like text-to-speech, subtitle generation and background removal, too, so it's a good option if you want to make a high-quality video.