Moon Phase Pro requests the following permissions from the Android system. Tap on any of the permissions – or just scroll down – for a detailed explanation of exactly what Moon Phase Pro is doing with each.

YOUR LOCATION: APPROXIMATE (NETWORK-BASED) and PRECISE (GPS)
Moon rise and set times depend on where you are
FULL NETWORK ACCESS
To look up locations, and to download the imagery used for Maximum Realism style
MODIFY/DELETE USB STORAGE or SD CARD CONTENTS
To store various images for faster operation
RUN AT STARTUP, SET WALLPAPER
Essential to making the live wallpaper and notifications work
PREVENT DEVICE FROM SLEEPING
Required for the Android Wear watch face

APPROXIMATE (NETWORK-BASED) LOCATION

Displaying moon rise, set, and rotation angle – as well as virtually every item on the Data screen – requires the app to know roughly where on Earth you are. So, Moon Phase Pro requests your approximate (or coarse) location from the Android system, which can usually supply it quickly – and with little battery use – from your network provider.

PRECISE (GPS) LOCATION

Ordinarily, Moon Phase Pro is perfectly happy to use your approximate (network-based) location; the low accuracy is more than sufficient for the app’s purposes. See the previous permission for more details on this.

However, a problem arises when you don’t have network coverage, or when you’re roaming on a network which doesn’t provide location services. The app still needs your location, and GPS is the only other (automated) alternative. For people who use the app in remote areas – say, when camping, or traveling overseas – this is the only way the app can get their location.

So, the app requires the GPS permission. But it doesn’t actually need your precise location – and you are free to turn off the GPS interface, either within the app (Settings > My Location), or system-wide on your device. You’ll just be limited to network-based location services.

Finally, rest assured that the app won’t power on your GPS if you’ve turned it off at the device level. No app can do that unless you’ve rooted your device – and even then, Moon Phase Pro won’t.

FULL NETWORK ACCESS

Moon Phase Pro has two functions which require internet access.

First is location search; by querying internet search services, the app can look up (and thus show moon data for) virtually any city, town, or other generally-known placename. This allows you to use Moon Phase Pro's features for just about anyplace on Earth.

Second, there's an option in Settings for Maximum realism, which gives a more realistic view of the moon on compatible devices. It doesn't work on all devices, though – and the imagery used for it is relatively large – so to keep the size of the app down, it’s only downloaded on demand. This occurs once, when you first select the this option; thereafter, the imagery is stored on your device, and won’t need to be re-downloaded.

MODIFY/DELETE USB STORAGE or SD CARD CONTENTS

The exact wording of this permission varies by device, but it means the same thing: the app has the ability to read and write your device’s user data storage, be that an SD card, USB drive, or internal storage.

Moon Phase Pro uses this ability to increase the speed (and decrease the battery usage) of its operations. It’s a graphically-intensive app, and creating the various graphics can be a load on the system. So, the app goes to great lengths to not create graphics more than it has to; instead, it saves copies of these graphics for future use. This is best done on your device’s user storage, so Moon Phase Pro needs permission to do so.

The app does its best to manage this storage use, and not use too much. If you want to delete these files manually, you can do so from your device’s system settings, under Applications > Manage Applications > Moon Phase Pro > Clear Data. These files will also be deleted automatically by the system if you ever uninstall Moon Phase Pro.

RUN AT STARTUP, SET WALLPAPER

The app’s live wallpaper is among its most popular features, and Moon Phase Pro is unusual in that it supported live wallpapers before the Android system did. This is still applicable to some lower-end devices, which don't support live wallpapers at the system level – but in order to make it work, these permissions are required. The app needs to start at boot to get the wallpaper process underway, and then set wallpaper to actually make it happen.

The start at boot permission is also used by Moon Phase Pro's notification system, for much the same reason. When there is a notification due, the app needs to be running in order to send it, and starting with your device is the only way to make this happen.

PREVENT DEVICE FROM SLEEPING

Moon Phase Pro includes a watch face for the Android Wear smartwatch platform, and that interface requires this permission to function. Please be aware that this permission is not used on your handheld device, only on the watch (if you have one). However, Android Wear requires that any permission used on the watch also be given to the linked handheld app, which is why this one's here.