The icons in question are located in what many people call the status bar - it shows the status of the device. The lock icon in an arrowed circle is the rotation lock, I'm unsure of the other icon. The rotation lock can be removed by double-pressing the home button > swipe the multitask bar to the right > and tapping the left-most icon (the same icon as in the status bar). This will unlock the device's ability to rotate the screen between portrait and landscape modes. Locking screen rotation serves to lock the screen orientation into a specific mode so that some apps, such as Safari, won't rotate when the device orientation is changed.