This app was mentioned in 3 comments, with an average of 1.00 upvote
Unity will work for that. I made a game completely with UI elements. No 3D or 2D specific components were used.
You can can use Unity's mechanim functionality to create animations for your 3D stimulation. Then call the animations from code when needed. The asset store also has cutscene managers, I have never used them so I cannot recommend one.
Here is a link to the game. I'm sure it's not related to your project but it shows you animations, layouts, etc. that are supported by Unity's UI system: https://play.google.com/store/apps/details?id=com.nomoreanalog.worldofwords
Cool game. I like it that you can pick the category to play. One concern though is that every few times I open the app it crashes. Using Nexus 6 Android 6.0.
Check out the game I made. It's a word game too but the game play is different: https://play.google.com/store/apps/details?id=com.nomoreanalog.worldofwords
A tiny man...
Check out my word game for Android: https://play.google.com/store/apps/details?id=com.nomoreanalog.worldofwords