Ltd. My Android phone is currently version 4.5 currently, the phone works perfectly on my Android. Unfortunately Amazon locks yes Google from their Kindle from Firefox, so that one is dependent on the Amazon Store. There, however, a completely outdated version is offered, not 4.3 as stated in the program name, but I was quite amazed as Antutu startup logs with version 3.4. Sorry seems to minimum my Kindle Firefox to dislike this version, because the benchmarks hung immediately on the beginning of the feast. Therefore, unfortunately unusable.