App Bak APK

Simple way to back up a list of installed applications to a file on your SD
card. The option to restore individual apps from this list is limited to other
app stores that are installed on the phone that can accept market intents. It is
not a good idea to restore apps already in the F-droid repo using this method.
In most cases F-droid apps will have a different signature requiring you to
uninstall the app when switching between sources.

There is an option in F-droid to cache downloaded apks to local storage, so if
you are looking to restore apps after a wipe try keeping that enabled. The apps
can then be restored using a file manager like https://f-droid.org/packages/org.openintents.filemanager.