checklist of, 'Things to do'.
1. Sound (Music, Effects)
2. Get the score system sorted out, no one wants a "NaN" score.
3. more weapons, and stop trying to rip me off for charging $88 for an upgrade that doesn't change ANYTHING
4. MORE ENEMIES!!!!
5. If you have the time, and quite plainly, the skill. try and remove the limit of waves.
I spent 10 minutes filling each and every block available and filled them with cannons, because I thought that eventually, it would come to wave 200 and the enemies would be at like a million health...
...but no. Come wave 36 and they go from 15k all the way up to 30k, That got my hopes up. then nothing appears.
Nice try, but if you seriously want to create a half decent game i'd spend a little more time on it.
10/10 for being originality.