Interesting game and fun~

<THIS REVIEW CONTAINS SPOILERS! READ AT YOUR OWN RISK>

Not bad!
The game has no real glitches and the game is a good test of one's patience and concentration.
After about a half an hour and several failed attempts I was able to catch all of the flies and got to the end screen, so the game is 100% beatable.

The only thing that seemed a bit off was that the Salamanders' tongue would sometimes go nowhere near as far as I had clicked. Not sure if this was deliberate to keep me on my toes with some RNG, or if it's just my computer bugging out temporarily.

I was able to get a good amount of fun from it, but as it stands the game is a little bit limited in terms of animation and extra things to do.
I can play the game as many times as I want, sure, but to help improve the games' longevity, it wouldn't hurt to try adding some extra game modes or challenges.

You're probably all finished with this game, but if you ever decided to make a sequel or revamp this game, here are a few suggestions that I'm sure would make it better.

-The tutorial at the start is short, sweet and to the point, but afterwards it should lead to a small menu with options and different modes to play before starting the game.
-An options menu could allow things such as sound muting, song changes and different colours for the flies. Customizations or different Salamanders? You name it! It would help people if they got tired listening to the same trance song while they played.
-The Salamander is always clinging to the wall perfectly still, even before it explodes in a violent burst of light. Adding a quick intro animation of it climbing into position (like Salamanders' do in REAL LIFE :D ) might help to give it some charm and personality, make me NOT want to accidently cause it to blow up.
-The end game screen isn't the most exciting victory screen I've ever seen. Perhaps a small sound effect and some fireworks, or even a song change would help the sense of accomplishment seem a bit more impressive and lively.
-More modes...
---Survival Mode - With a score counter and endless flies
---Timed Mode - Endless Flies, how many can you catch with custom time limits?
---New Game + - More flies, more colours, more focus needed.
---Challenges - Never catch a flie with a unique colour that flies rapidly everywhere, it won't leave you alone!
---Hurry Up Mode - Waiting too long or being too cautious will occasionally cause more flies to show up. Can you spot an opening fast enough?
-An animation of the Salamander squiggling when it catches the wrong colour of flie, he tastes his mistake and realizes he's about to go boom, maybe he should panic. haha

Nothing wrong with a focus test game, but with some tweaks I'm sure it can be a lot more impressive. Keep it up and keep improving!

you should put a number somewhere so we know how many flies are left before we win ^^

Very cool little concept, but I think you should expand it a bit, just like with Hexpulse.
You could for example make the flies a bit bigger and make their movement more complex instead, because it just doesn't feel very comfortable to click on them.
And of course all the other things that would feel the gap usefully up, such as score ( in-and outside game), powerups that make you go epileptic and pick any flies you want for a certain ammount of time, a bit more complexity etc.

rrAAAAGGHGHGHGHG I love this game god dang it it's addictive