Hi Vincent. Thanks so much for getting the game and leaving some feedback!
Unfortunately there is no endless mode at the moment, it was in fact part of my original idea for this game but when the rest of it broadened in scope considerably I decided I wouldn't be able to include it.
However... I'm wondering if I can find a way to add an endless mode, or even to create a separate game using the same base code purely for endless (if so I'd put it here free for existing owners). I'll have to think about it.
I'm glad you're enjoying the game. It certainly gets more involved after you get past the first few levels :) I tried to make the levels feel reasonably different with specific challenges even though obviously the main thrust of the game is the same throughout.
Hope you continue to reboot the game!
Thanks again,
Dave