Dioptra™- a camera position and angle measurement tool for navigation, surveying, positioning, and measurement.
Celebrating 30,000 users in 2016!
Instructions: Press the on-screen camera button to save an image. View saved images in your device's gallery app.
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Dioptra™ provides the following information like a theodolite optical instrument -
• yaw indicator (compass)
• pitch indicator (tilt degrees)
• roll indicator (tilt degrees)
along with -
• GPS position
• azimuth and bearing to photo subject

The ancient greek "dioptra" was a classical astronomical and surveying instrument, dating from the 3rd century BCE. The dioptra was a sighting tube or, alternatively, a rod with a sight at both ends, attached to a stand. If fitted with protractors, it could be used to measure angles.
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