We are so sorry to take too long to reply to your issue, yes, we have received many feedbacks that they are very confused about the SDK's names, it's our fault, and here's the answer: the kendryte-standalone-sdk includes a lightweight freertos implement, and the kendryte-freertos-sdk now is becoming a more complicated OS, if you are familiar to freertos, the kendryte-standalone-sdk may be better, if you are not, maybe the kendryte-freertos-sdk is simpler. We are considering changing the name of kendryte-freertos-sdk to something else to prevent more confusions.