But how about the ability & quality of these apps when handling video recording task in the old device? Here's a quick comparison from 4 apps I consider the best plus 1 from Cydia (jailbroken iPhone).
Qik VideoCamera ($0.99) (link iTunes & website)
iVidCam (free & $0.99) (link iTunes & website)
iVideoCamera ($0.99) (link iTunes & website)
ShowTime ($0.99) (link iTunes & website)
VideoRecorder3 ($19.95) (link website)
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Summary:
Qik Video Camera
Pro: Better frame rate, save to Camera Roll, H.264 compression
Cons: Portrait recording only
iVidCam
Pro: Biggest frame size, 10x digital zoom, free version is available
Cons: Only upload to YouTube
iVideoCamera
Pro: Upload to YouTube, Vimeo, Facebook, email & save to Camera Roll
Cons: Smallest frame size, limited recording time
ShowTime
Pro: 5x digital zoom, share via email
Cons: Portrait recording only
VideoRecorder3
Pro: Upload to YouTube & email, best frame rate, MPEG4 compression
Cons: Expensive, only for jailbroken iPhone
Go get one, give your old iPhone another chance to reveal its true ability.