Now I know where the Size Matters frog comes from! :)
As for the game itself? I hope you'll forgive me, but honestly, I can't say the design is good. There's no fluid movement or much strategy. Moving on a grid-based system feels stiff and punitive. Underwater, you can move left and right simply enough (not smoothly), but it doesn't help you get into a flow. The hit detection for the fly seems wonky, seemingly missing when it's touching the fly when not simply difficult to line up, since the there's no way to aim the narrow tongue, so you have to eyeball and hope for the best, and the heron barely telegraphs the bite by just briefly appearing with an open mouth above you for a split second, making it nearly impossible to react, and it's suddenly over in one confusing instant. If you do react in time, you'll still probably die, as you explicitly have to remember to press down, which isn't obvious as your first instinct is to chase the fly, that getting the fly automatically saves you, and there's nothing visually enforcing that you can only go down while above water for some reason. You just have to remember, so it feels like you get stuck a lot. And that's when you're not just missing the fly or dying instantly.
While the concept of a simple arcade game of being a nimble frog to pop out of water to catch flies to avoid a bird works well enough for this arcade game and could be interesting, there's really nothing to keep you engaged. Just a high score number, and that's it. One static challenge, nothing dynamic or interesting, and no possibility for interesting anecdotes.
The best part of the game is the aesthetic style. They're not bad, but they're not interesting. The retro pixelated style is nice, but there's not much to look at. There's the title screen logo, the hastily slapped together default buttons, up to three frames of animation per basic sprite, inconsistent black or white outlines, and the curvature of the fly's path. The sound too is nothing special. The music's fine, not amazing, and the sound effects are underwhelming. At least the details of the rewarding, exaggerated Minecraft chewing sounds in tandem with the frog sprite chewing, and the clown honk with trying to eat underwater are cute.
I'm afraid to say the game is pretty messy. With the gamey abstraction and confusion about mechanics, the distractingly modern sounds vs retro arcade noises, and a decent pixel style contrasting default menu UI, it tends to fall apart.
I can't honestly say I had much fun with the game. On the occasions I could get into a flow with the stiff controls, I tended to die in an instant to the heron, and seems to mostly be an exercise in precision. Mostly, the game left me bored when it wasn't frustrating. My high score was 15 and I didn't care to go beyond that. Finishing a game in 48 hours is always a feat, so props to you for taking on that challenge. Perhaps with some polish to could become a viscerally satisfying challenge. But for me, this game wasn't it.
Terminate 
GÖRF 
Run as administrator 
The Lumlings Welcome You 
Dark Cut 
the classroom 
gunshot soundboard 1.1 
Underage Driving 
Dynasty Street 
Crimson Eve 
