Inner angles of an area

Is that corner of the plot really square? Does the field match the angles on its plan? Turn on angle annotations, and every corner of an area shows its inner angle, right on the map, next to the side lengths.

Turn it on

Open MENU > ⚙️ SETTINGS, choose the Annotations tab, and set Show angle annotations to YES. While you edit an area, the settings button between the perimeter and the area values at the top of the map opens the same Annotations tab. It is off until you turn it on.

What you see

• A label inside every corner, in whole degrees, such as 92°.
• A corner that turns inward shows more than 180°. In the field above, the fourth corner reads 274°: the land goes around it, as in an L-shaped plot.
• A point on a straight side shows about 180°. That is correct: the side does not turn there.
• The labels stay inside their corners when you zoom or turn the map.
• Areas only. Routes and circles have no corners to measure.

Angle labels appear together with the length labels, while the map is not following your location. An area with more than 400 points (100 on the Google map) hides its angle and length labels, and the app tells you why.

Check a measurement with it

• The angles add up. The inner angles of an area always total (corners − 2) × 180°: 360° for four corners, 540° for five, 720° for six. The field above: 100 + 92 + 70 + 274 + 83 + 101 = 720°. A total far from that means two sides of the shape cross: check the order of its points.
• Square corners. A building footprint, a fence line or a garden bed should show 90° where the plan says so.
• Against the plan. Compare each corner with the angles on a deed, a cadastral map or a site plan.
• A misplaced point. A sharp spike, such as a 15° corner where the land has none, usually means a point was placed or moved by mistake.

The angles are measured between the sides as you drew them on the map, so they are as accurate as the points you placed.