Starmap uses all the usual touches and gestures of the iPhone™ interface. Sliding your finger over the map changes the eye view direction. Using “pinch and zoom” modifies the field of view. Touching an object lets a short information panel for the object appear on the screen. Double taps are generally used to come back to defaults.

Given the large number of celestial objects included in Starmap and the relatively small screen of the device, Starmap applies a dynamic magnitude limit on the displayed objects, increasing automatically when zooming in the map.

The first  image (see figure 1) shows the Orion constellation at maximum field of view. After having pinched and zoomed on the Orion belt (see figure 2) more objects are displayed, with greater magnitudes.

With this principle, Starmap shows a constant number of objects on the screen and therefore keeps a high readability of the map.

The map appearance can be modified at your convenience. From the settings, the user defines what kind of objects are displayed, applies magnitude limits, changes colors, add coordinates grids and equators, among many other possibilities.

Fig. 1: Orion, at maximum field of view

Fig. 2: Orion, closer view. More details appear on the map

Starmap functions are accessible from the bottom menu bar (see figure 3). Press More to get access to all functions. The menu screen can be scrolled up and down. Touching an icon lets the related panel appear.

Functions are grouped by kinds. When going back to the map view, these will be directly accessible from the bottom bar. When modifying the settings, or looking for objects, similar functions are reachable without coming back to the menu panel.

For instance, when looking for a planet, the star catalogue will be added to the menu bar. When adjusting your optics, the Telrad will be displayed, and so on. The menu cannot be re-ordered.

At any time, using the back buttons on the top left part of the interface will bring you back to the upper menu level and finally to the map.

Starmap can be used in landscape mode (see figure 4). A larger field of view is displayed, and the menu bar disappears.

Once your optics configuration is defined, turning the device face down, and face up again swaps between the eyepiece and the mapmode. You will find this gesture very natural and practical while observing.

Fig. 3: Starmap functions are all accessible from the main menu.

Fig . 4: the map in landscape mode lets the menu bar disappear.