Another shooter in an esteemed list, “Twin Tiger Shark” is the first vertically-scrolling one from Mikael Tillander. It doesn’t reinvent the wheel, but nor should it. This is about quality over innovation. And the quality manifests itself in huge bosses, interesting special weapons (such as bringing in a squad of reinforcements via “helper planes”). And it supports controller rotation support which, though I haven’t tried it myself, I take to mean that you can put your widescreen TV on its side to more closely mimic the classic taller-than-wide vertical shooter arcade screens of yesteryear. That’ll zoom in on the (very attractively rendered) sprites, if you have a small (and durable) TV I suppose. Absolutely well worth a dollar.
Here’s what the publisher (Mikael Tillander) has to say about the game:
“Twin Tiger Shark is a biplane STG/shooter with its roots in the 80s. * TATE (Wide Screen 16:9) and Control Rotation Support * 6 Stages – 2 Loops * 2 Difficulty Settings * No Continues * 3 Weapon Types * Helper Planes * Smart Bombs The game is a tribute to a well known STG developer company of the 80s and 90s.”
Writings of Mass Deduction 
Or instead of playing it like a vertical shooter you can play it as a horizontal shooter. Although it plays better as a vertical shooter.