The time it takes to play words and to wait for the pyramid to form easily uses the bonus time gained. The timing isn't bad but you could allay the problem by pausing the timer until play is possible and maybe allowing the user to type the letters instead.
There's a single weapon in this game that's 2299 gems. If you buy 1000 gems, you get 100 gems for free (generous). That's 2 lots of 1000 gems with a little bit on top. But 1000 gems costs 1000 Kreds which, in turn, cost $100. Even more generously, you get bonus Kreds if you buy 1000 at a time, so it'll only cost you $200 for that sword.
There needs an ability to pause the game. The 5th tower is just a slower version of the 6th for the same price... that is confusing. Enemies that are appearing on the screen at defeat stay there when the end screen appears. The end-of-game screen needs a button to take you back to the main menu instead of having to refresh. It was alright but nothing worth more than a 2.
Unlike most people, I found the controls were fine. I first tried to look for keyboard controls but the lack of them didn't detract from the game. The only downside was that it was pretty easy thoughout which, on a side note, doesn't do wonders when it comes to convincing me to play the full version. All the same, it's a reasonably novel idea and I give you a well-deserved 4.
I think this game'd be much easier to play if the buttons to connect the bridges were on the islands or involved clicking and dragging in the direction needed. As they are right now, it looks much too cluttered.
done, both have a 50% increase(proportional to screen increase) along with the addition of music and screen widening.