A. Are you interested in developing software for the Yuneec H520? Here is the link to their SDK (Software Development Kit) portal.
B. Warning about ADVANCED MENU in ST16s. The 3 lines icon brings up the Settings/Info. If you tap rapidly 5 times the Advanced Menu will be available. DO NOT do this except under the direct direction of authorized Yuneec Techs. It is all too easy to make accidental changes that brick or crash the craft. Warranty will not cover this.
If you see this screen by mistake, back out or immediately turn off the ST16s.