The explosive rise of the shoot-'em-up - or 'shmup' for those with busy schedules - can be attributed to Space Invaders.
When it debuted during the late 1970s, it famously caused a shortage of 100-yen coins, such was its popularity in the Japanese arcades.
Dutch developer Firi Games's top-down survival shooter Phoenix HD isn't likely to panic the App Store's currency handlers in the same way, but it's a decent enough addition to the genre on iPhone and iPad.
Thrust straight into the action without a care in the galaxy, you guide a handsome ship through endless swarms by sliding a finger anywhere on-screen.
Should your cockpit attract the attention of an enemy projectile, you can regain health by destroying the opposition's turrets and collecting the resultant power-ups.
You can also pick up weapons upgrades, shields, and alpha strikes en route, with the last-named bonus best reserved, where possible, for dealing with the more ornate, unrelenting foes.
By virtue of the dev stripping the game down to the barest essentials and waiving the likes of buttons, continues, lives, stages, and modes, the bullet-hell action here is immediate and unencumbered, albeit divested of depth.
Who lasts longest?
While the absence of any complex strategy may well disappoint seasoned shmuppers accustomed to the gauges and scraping of DoDonPachi Resurrection, Phoenix HD, with its adaptive AI, ensures players of all skill levels can enjoy a modicum of success.
Its sweeping constellations of amber gunfire and intricately drawn spaceships shift along at a fair old lick, demonstrating no noticeable drop in frame rate on even my now-archaic iPhone 3G.
Whether you decide to replay this vertical scroller over and over again, though, depends heavily on your competitive spirit and, therefore, your willingness to climb those oft-alluring local and national leaderboards.
Phoenix HD offers nothing imaginative, deep, or innovative in terms of shoot-'em-up gameplay, and so takes a second seat to the bigger names in the genre despite its accessibility.