If you want to avoid the pitfalls of the above approach for the various mixers there are off course alternatives. One is David Schumann’s Mixing Station that now covers four brands and 24 mixers. Here is the list and blatant plug for Dave’s products. There are free versions but the pro versions won’t break anyone’s bank.
Please make sure your mixer has the latest compatible firmware.
App Mixers Required firmware Notes
XM32 Any X32/M32 mixer V1.15 or newer
XAir Any XAir mixer V1.12 or newer
Qu Any Qu mixer V1.90 or newer
SQ Any SQ mixer V1.4.1
GLD Any GLD mixer V1.61
Si Any Si Performer/Expression/Impact V1.8 / V1.8 / V1-2 See HiQNet guide
Wing Any Wing mixer Any Coming soon
He now covers Android, iOS, Windows platforms.
https://dev-core.org/mixing-station/There is however another solution and that is Soundcraft's Ui series of mixers. Christmas was a good time to check out the Ui24R version (another addition to my collection). Platforms only need a HTML5 based browser to work. This certainly eliminates the lock into iPads. Unfortunately Mackie’s BenO decided against providing Dave with the marvelously useless Mandolin protocol several years ago.