How many devices can simultaneously connect to the mixer's Wi-Fi?

I saw somewhere that the limit would be 6 devices, but not sure if I’m misremembering. Would this change if an external router is used?

Not likely. Device count limitations on SQ and Qu are from overloading the network stack.

I think I saw/heard somewhere that you can connect 2 CQMixPad apps and 6 CQ4You simultaneously.