If your device is unable to update to the latest iOS, follow these steps to install ForeFlight Mobile:
STEP 1. Open the App Store.
STEP 2. Tap the Purchased button.
STEP 3. Use the “Purchased App” search bar in the upper-left corner to search for "ForeFlight."
Note: Do not use the search bar in the upper right-hand corner.
STEP 4. Locate ForeFlight Mobile EFB and tap the cloud symbol.
Note: If ForeFlight Mobile EFB is not listed in your Purchased apps, download ForeFlight Mobile from another iOS device while signed in to the same iTunes (Apple ID) account and then repeat the steps in this article.
STEP 5. Tap Download to begin downloading the last compatible version of ForeFlight Mobile EFB to your device.
NOTE: Depending on the device and iOS version, you will be prompted with the message "Download an older version of this app" or "Do you want to download the last compatible version?" In either case, tap Download.
See "What version of ForeFlight can be installed based on the version of iOS on my device?" for details on which version of ForeFlight Mobile works with your version of iOS.