Assume that your are doing measure your object start from left side and move to right side.
Step1:
Initialize the ruler with tap
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[Buttons]
It has 5 buttons and one needle.
It is a clear button to reset ruler.
It is a button to change ruler direction.
It is a button to swap "cm" and "inch".
It is a button to move ruler position to current position plus the length from start point of current screen to needle.
It is a exit button.
It is a needle to where the number points.
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Step 2:
Put your left-end side of ruler screen to the left most end side of the object to measure.
Step 3:
move to right most side of the screen.
Step 4:
Put your index finger to the needle point position.
Step 5:
Move to left-end side of screen to match your index finger.
Step 6:
Repeat step 4,5 and 6 again and again until the right end of object is located inside the screen.
If the end of object are located inside your iPhone or iPod touch screen,
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[Buttons]
It has 5 buttons and one needle.
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