Both updates bring that Kit Kat fire, which includes a revamped lock screen, restyled notification areas, expanded emoji support, wireless printing, default SMS chooser, and Samsung KNOX 2.0. Isis Wallet is also now pre-loaded on the Galaxy S3 and a bunch of bugs have hopefully been squashed for both phones.
You can find the full changelogs for both below.
If your device does not see the update today, be patient, these things typically rollout over the course of a week or so.
Galaxy S4 Mini
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