Samsung Galaxy S and S2 owners shouldn't get excited with Android 4.4 KitKat "running older devices" for Samsung may not release a new firmware to both smartphones. There are five possible reasons why it is not possible or why the two devices ineligible are ineligible for the update.

Update Window Period

Samsung Galaxy S GT-I9000 was released on June 2010, while Galaxy S2 GT-I9100 succeeded Galaxy S on April 2011. Both smartphones are expired and aged the given 18-month update window period that is usually used by manufacturers. In addition, several newer Galaxy smartphones running Android 4.1 are likely to get the update than Galaxy S or S2.

TouchWiz UI Version

The Galaxy S features TouchWiz 3.0 and Galaxy S2 runs TouchWiz 4.0 user interface that are 2 to 3 years behind TouchWiz 5.0. The Galaxy S3 suffered integration of TouchWiz 5.0 on Android 4.3 Jelly Bean firmware, which features several exclusive stuffs from Galaxy S4 and Note, 3 this year. Samsung will likely not waste much time to integrate Android 4.4 and heavyweight TouchWiz 5.0 UI on the Galaxy S and S2.

Android 2.3 and 4.1 Upgrades

Android 2.3 Gingerbread is the highest available upgrade for Galaxy S from Android 2.1 Éclair. The Galaxy S2 is fortunate enough to get Android 4.1 Jelly Bean from Android 2.3.4 version, right after Android 4.0 ICS. It also means that both phones weren't included in the latest Android 4.3 push update which makes their current OS final.

Galaxy S3 and Note 2 Android 4.3 Releases

Android 4.3 Jelly Bean is out for the Galaxy S3 and Note 2 with Galaxy S4 and Galaxy Note 3 exclusive apps, but Samsung didn't include the first and second generations of Galaxy S series with the rollout. Moreover, Samsung UK is busy dealing with Android 4.3 upgrade in their region which is currently on hold. It seems like there isn't much attention left for the Galaxy S and the Galaxy S2.

Android 4.4 KitKat Priority Devices

Android 4.4 KitKat is confirmed on the Galaxy S4, Note 3, Galaxy S3 and Note 2, according to a recent leaked document. January 2014 is the date scheduled for update rollout for the Galaxy S4 and Note 3, while Galaxy S3 and Note 2 will receive the new major update from March to April next year.

The Galaxy S and S2 are both powerful smartphones during their time as flagship devices, but the Galaxy S3 succeeded its capabilities with partially "futureproof" ability that can run a future Android version without any problems on hardware components. If you want Android 4.4 KitKat, consider obtaining the Galaxy S3 if not the latest S4 smartphone.