Remember the HTC EVO LTE? Sprint does, at least to some degree. The carrier is sending out a small software patch for the phone, reportedly removing a vulnerability from the infamous Heartbleed SSL security bug. Unpatched versions of Android 4.1.1 (and only 4.1.1) are vulnerable to Heartbleed, so EVO LTE owners probably want to get on that right away.
Heartbleed's relationship to Android is a little strange: it affects Android 4.1.1, but not earlier versions of Jelly Bean 4.1, and not later versions of any release, either, so the number of active phones and tablets at risk is comparatively small.