Small white flash occurs when switching between apps
I dropped my iphone and cracked the screen. After I got it repaired at a local shop I noticed that sometimes when switching between apps that in the middle left-hand side of the screen a white flash occurs. This doesn't happen every time but it is repeatable and seems to happen more over time. Doing a reboot causes it to happen less. This is definitely not the flash seen when taking a screenshot.
Also my battery life has been worse.
iPhone 5, iOS 7.1