iFly GPS Forum

iFly does only update charts that have changed.  You can tell this because if you update frequently, you will notice dramatic differences in update package sizes.  (If you update infrequently, you may be more consistently seeing that "everything" needs to be updated.)

Walter has previously addressed the limitations AP faces in getting updated data out any earlier than they do.  Doesn't seem likely that will get much better.  (Though I'm scratching my head how downloading updated data 5 days before expiration vs. 3 days before expiration makes the update process any faster.)

I don't have any other EFBs, so have nothing to compare it to.  I only have a few states routinely selected (though one is Texas, which takes way longer than the states adjacent to it), and the updates typically take me ~7-10 minutes.  If I go a long time between updates, or take a cross-country that adds several states to my package, then that can drive the time up to 15-20 min.

The bits that seem to take the longest are the first few things that get downloaded:  Weather, software updates (only happen occasionally for production, but are frequent for beta testers), and maybe something else...aviation databases, perhaps?  These take a lot of time because they involve a bunch of small files, and something about that part of the process takes time (I'm not sure if it's just the process of printing all the filenames to the screen for status reporting that slows it down, or actually extracting/moving those files that takes time, or if each individual file is getting downloaded separately, or what).  Regardless, the "average download speed" number plummets during that part of the process (can get as low as 100-300 kps), and the projected time to complete the download looks scary big. 

However, I've learned not to panic and to wait until it gets through that part before believing the time predictions.  Once the process gets past that slow stuff at the beginning and on to downloading the charts and plates that make up the bulk of the download, the average download speed ramps up dramatically (usually 2000-3500 kps), and stays that way through completion.

If you are routinely downloading all possible data, then that can take a long time, especially if you have an IFR subscription.  I learned a long time ago that dropping off Alaska, the Pacific Territories, and about 40+ states that I'm not planning to fly to anytime soon can save a lot of download time!