Thanks so much BeaverMode, this is really helpful feedback!
Great news - I just pushed a big update (v5) based on feedback like yours:
- Better difficulty curve: water budgets are much more generous in early levels now, so level 3 should not be a wall anymore
- Improved tutorial: hints persist longer and there is a help popup on levels 3-5 explaining the wrong-color penalty
- Better progression: 20 levels with smoother difficulty scaling
- Power-ups: great suggestion! Added water bonus pickups in later levels
You are totally right about mobile being the sweet spot - it is built mobile-first and the swipe controls feel way better on a phone.
Would love if you gave v5 a try and let me know if the difficulty feels better now!