Iphone slow-down? – BOSS Tuner Review

This tuner worked so well I was considering leaving my other tuners out of my guitar cases. However, a few months ago, I suddenly found that the tuner was off. It now registers my 440 tuning fork as about D#. Apple recently admitted it slowed down older iphones, which they may have done to my iphone (through IOS updates I installed?) and caused the tuner to read about 3/4 what it should. If you are going to load this on an older iphone, perhaps the IOS "updates" will screw it up.
Review by Phil Phlorida on BOSS Tuner.