Direction explorer Downloads & RevenueDirection explorer · App Store

DirectionExplorer combines a compass tool with Apple Maps by Apple to help you identify targets (villages, buildings, mountains, and more) appearing in your view.
DirectionExplorer uses GPS to determine the observer's location and, using compass information, draws a line on the map in the same direction the iPhone is pointing. 
The heading line includes distance marks, allowing you to better estimate distances directly on the map.
You can freeze the origin point and direction line to study the map in detail later. You can also determine the length of the heading line (in miles or km) to better estimate your field of view. The horizon distance can be automatically calculated based on the site's altitude.
The point of origin can be entered manually by tapping the map.
To help you find desired targets more easily, you can insert colored pins above the map. Pins can be set by tapping on the map or by entering place names. Tapping on a pin or on a mountain displays an information box with detailed data about the selected target and these data can be easily shared.
From an offline list of mountains, you can choose which peaks to display on the map. 
The information box also suggests possible obstacles (based on the offline mountain database) that may lie between you and the selected target.
For best results, hold the iPhone horizontally and aim accurately. 
It is also important to periodically check the compass calibration and follow the on-screen calibration instructions.