The most useful thing about undet is that it can manage all your 3D models in one place so you don't have to keep track of multiple applications or platforms.
It's easy to use as well since I'm not very techy when using my phone which makes everything easier! Nothing really. Sometimes it takes longer than necessary but other times its quick enough if you know how quickly things are going along. If anything i would suggest getting this app just because of ease of access and managing different files from anywhere at any time compared to others like Sketchup etc.