
iOS 9.3.3 is listed as bringing a few bug fixes and improvements to the latest iOS 9.3.2 public firmware. The previous firmware was responsible for bringing a Bluetooth fix to the iPhone SE and some improvements to Low Power mode.
WWDC is right around the corner, meaning that iOS 9.3.3 should be released to non-testers very soon. Apple is expected to show off iOS 10, or iOS X, at its keynote, which should release alongside new devices in the fall.