ForeFlight mobile alone, takes up very little space (less than 500 MB), but once you start downloading charts, maps, documents, and more, space required will increase. With ForeFlight Mobile, you can store airport diagrams, terminal procedures, and navigation charts for the United States and Canada for use in flight. The Downloads page (More button > Downloads) lists the approximate size of each download so you can estimate how much space is required for your selections.

Download sizes can vary greatly, depending upon your selections, but a good rule of thumb for the USA is that each state requires, on average, 320 MB to download all items (i.e.: Terminal Procedures, IFR and VFR charts, WAC charts, High Resolution Terrain, etc). Alaska is the exception, requiring around 2.3 GB of space. Canada requires, on average,590 MB per Province with all available items selected.

If you want to download everything available, plan on the USA lower 48 States and Hawaii taking about 14.7 GB and Alaska taking up about 2.3 GB of storage space. Canada will require about 9.8 GB for all available downloads.

Required downloads, included in the figures above, require about 850 MB of storage space.

A few items displayed on the Downloads page display a compressed file size. This means the actual size, when de-compressed (un-zipped), will be larger when the file is installed. The compressed items are as follows:

– United States (lower 48) high resolution terrain is a 242 MB download and takes up 1 GB on disk.
– Mexico/Caribbean/Central America high resolution terrain is a 98 MB download and takes up 737MB on disk.
– Canada high resolution terrain is a 334 MB download and takes up 1.4 GB on disk.
– Alaska high resolution terrain is a 52 MB download and takes up 947 MB on disk.
– Worldwide low-resolution terrain map is a 61 MB download and takes up 320 MB on disk.
– Airport Database is a 60 MB download and takes up 460 MB on disk.

Approaching a chart cycle changeover date, pilots usually download the data update a few days before the 28 day changeover. Because of this, it is possible to have have a temporary condition where nearly twice the normal size of data is stored on your device (i.e.:14.7 GB becomes 29.4GB) during this time.

Downloading all of the documents and handbooks available in the United States subscription requires almost 1 GB of space.

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