This package gives you easy and fast access to a fully packaged dynamic level selection project, you will only have to delete the level scenes, and add yours, the Level Text variable within World 1 and World 2 Levels is going to be the actual scene number, the Just Text variable within World 2 Levels is going to show the text for the level in the button because the Level Text is going to launch the scene with that number.

For example, the first level on World 2 is showing the text 1, but the actual level text is 11 because it is going to launch the scene with name Level11.

So you can set it up to have in World 1 levels up to 10 or 20, and show the text for the levels on the buttons 1-20, and on World 2, it will also show levels 1-20 but the actual Level Text is going to be 21-40.

Just make sure your levels are within Scene and then Levels and name them Level1, Level2...and so on. Also make sure to set the score like in the PauseScreen code to send back the score globally like this code:PlayerPrefs.SetInt("Level" + CurrentLevel.ToString() + "_score", score);

The code should work fine on Android as I have developed a game and used and it is working fine, check the game if you would like to test before purchasing:
https://play.google.com/store/apps/details?id=com.Asenderov.REDBEARDStudio&hl=en
Let me know if you have any questions, and note that I have watched a lot of tutorials to develop this dynamic level selection, you may search on youtube.com to get close results to mine but I modified the code to suite my game's needs. So again, no need to call me a theft or anything, I can provide you with links to build something very close to this project, but it might take you a couple of hours.
Price is changed from 15.00 to 10.00