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| The iPhone 4S Portrait Orientation Lock prevents your screen from shifting to landscape mode when you're reading and lying down. |
How do you lock portrait orientation in iPhone 4S when the screen orientation automatically changes with how you hold your phone? In Messages for example, you can type in landscape or portrait orientation by just holding the phone sideways, or upright. This landscape-portrait orientation shift happens automatically. But what if you're lying down? You're going to be holding your phone sideways and so your screen shifts to landscape orientation. How do you lock it to portrait orientation so you can type and read stuffs upright?
Step 1. You can lock the portrait orientation in iPhone 4S by first double clicking the Home button. Four of your recently used apps will appear at the bottom of the screen.
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| The recently opened apps will appear by clicking the Home button twice in iPhone 4S. |
Step 2. Now swipe right over the apps and you'll end up with five icons (left to right): The Portrait Orientation Lock, three music control buttons, and the Music app. The Portrait Orientation Lock is the leftmost icon with the circular arrow symbol.
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| Swipe right over the recently used apps to find the Portrait Orientation Lock icon. |
Step 3. To lock the iPhone 4S screen in portrait orientation, select the Portrait Orientation Lock icon. A "lock" will appear inside the circular arrow, and the status 'Portrait Orientation Locked' will briefly appear below the icons. Select the Home button again to exit.
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| The Portrait Orientation Lock icon, once selected, will show a "lock" symbol inside the circular arrow. |
Notice that the Portrait Orientation Lock symbol will also appear in the status bar right at the top of the Home Screen and between the time and the battery level symbol.
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| That "Portrait Orientation Locked" symbol appears in the status bar when it is enabled. |
With the portrait orientation locked, you can only type, browse photos, and read in upright position. Of course, apps that are developed and released in landscape view cannot be "forced" to portrait. To disable the portrait orientation lock, just repeat the three steps above. When you do that, the "lock" will disappear from inside the circular arrow symbol in the Portrait Orientation Lock icon, the status "Portrait Orientation Unlocked" will confirm your action, and you can start shifting between landscape and portrait orientations again.
Additional info: It is the gyroscope inside the iPhone 4S that senses and maintains the screen orientation using the concept of angular momentum (Google is your friend). Circuits inside your phone receive the gyroscope output, feeds it to your firmware, and your firmware decodes the output and shifts the screen orientation accordingly.