How to use the iPhone as a water level

There's a level in your iPhone! This will be useful if you need to hang a painting or want to know if a table is level. You'll find the passcode hidden in the Compass app, and in this tip we'll explain what you can do with it.

iPhone as level

In the past, there were special apps that enabled you to use your iPhone as a passport. Since iOS 7, they have become redundant, since since then the passport is standard on every iPhone. This allows you to measure whether something is candlelit. To do so, start the Compass app on the iPhone and wipe across the screen so that the level of the passport appears. There are two ways to use it: put the iPhone flat on the table or put the iPhone on its side.

Use water level lying

Do you want to see if a table is lit or you want to plaster a floor, then lay down the iPhone flat. You can see two spheres, which must overlap exactly. Once this is the case, you will see the digit 0 and the screen will turn green.

Use water level standing

If you want to know if something is right, put the iPhone straight or on its side. Standing is handy to straighten shelves and paintings. You can see what angle your iPhone stands for and move around to make sure it's zero.

Use water level to compare

Suppose you want to place two planks at an angle of 48 degrees. No problem! You can also use the level on your iPhone. Measure the first item and tap the screen to 'capture' this measurement. Then you can use the numbers on the screen to determine how obliquely the second item should be, as shown in the image above. The compass also allows you to lock the measurement so that you can compare two measurements.

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Source: https://www.iculture.nl/tips/iphone-waterpas/