Craziflie 2.0 not respond to iOS client

[ocb00999]

I just assembled the craziflie, and I downloaded the iOS app. I tried to control the flie from my iPhone 5s. Bluetooth was turned on and the flie was connected. However, when I tapped my two fingers on the screen and moved around, nothing happened to my drone. Anyone know why is that?
I can see the M4 led is blinking green quite rapidly, M2 led is blinking red rather slow, M2 and M3 are always blue.
Thank you.

[ocb00999]

OK, I seem to have found out the trick. Every time I restart the flie, I need to place it horizontally, only after I do that it will start to accept the command.
Is that something bug or maybe a safety precaution?

[chad]

When you turn on the Crazyflie is does a number of self-tests on its sensors. You need to make sure it is horizontal and undisturbed during this process.

I've moved this thread to Crazyflie->Support forum.