Since version 3, TeX has used an idiosyncratic version numbering system, where updates have been indicated by adding an extra digit at the end of the decimal, so that the version number asymptotically approaches π. This is a reflection of the fact that TeX is now very stable, and only minor updates are anticipated. The current version of TeX is 3.141592653
I wish.
Sadly the google play store requires monotonically increasing build numbers, so any option of resetting build numbers after major releases goes out the window.