Any recommendations about how to approach this?
Goal: Would like to use an iPhone or iPad to trigger KM macros, using gestures. Don’t have a preference if it’s using an app or directly using MIDI CC.
Also open to alternatives, Metapad looks like an option.
I’m testing BTT and BTT remote but the app is appalling, I feel puzzled trying to find my way around their unfathomable interface decisions…
KM does not support gesture trigger yet, does it?
BTT does support, but it has to know what gesture is made on the iOS device.
An app like this may be useful, but I'm not sure.
Instead of gesture, why don't you try something like TouchPortal?
I've been using it for a while. It's quite useful. You can design numerous buttons.
Yes - see trigger:Gesture [Keyboard Maestro Wiki]
But that’s not necessarily what @hello is after!
I use voice commands (Siri Shortcuts) or this app:
Thanks everyone.
I found this video by @appleianer at the BTT forums
Very useful indeed, learned more in those 5 minutes than hours of banging my head with BTT!
As for now, I can use BTT Remote in the following way:
1- Do a 3 finger swipe, this
2- Opens Gesture window
3- Do a gesture in BTT Remote
4- Trigger a KM macro following Appleianer's guide
Oh nice, discovered that with BTT Remote I can have both ways of working:
Video about buttons :
@hello unfortunately it is not (yet) possible to run script on Mac in BTT Remote.
I now prefer Siri shortcuts to run various KM macros.
Here is an example how I start a call on the iPhone and activate DND on the Mac at the same time:
Another example would be to use a Siri shortcut (Hey Siri) to unlock the MBP and start my radio stream and then stop it as well:
Maybe you just want to quickly take a picture/document with the iPhone and forward it to the Mac 
When this is not possible with the Siri voice command (office, meeting, etc.) I execute them via the MFC Deck app,
I just had it working @appleianer, following your video. A Mac script(AppleScript) triggered from the iPad.
Will post a video, but it’s just a KM macro triggered using a BTT Remote gesture drawing.
Example:
In BTT Remote (iPad), I do a swipe down using 3 fingers,
This triggers a Drawing action in BTT
Then, I do an L drawing
that runs the AppleScript
In the Mac:
The drawing overlay opens
The gesture (L) appears as I start drawing it in the iPad
The gesture is recognized
The AppleScript runs, calling a KM macro using its UUID
Edit:
for completeness, the BTT macros:
BTT Remote: Swipe gesture to display the overlay:
BTT: Drawing gesture to run the KM macro:
@hello one learns nevertheless again and again. Now I have been using BTT for several years, but I have never paid attention to the BTT Remote Trigger setup.
Thanks for your tip 
Glad to have given something in return for all your great tips!
Thanks. I totally missed that!
I tried to make it work but never succeeded.
BetterTouchTool's gesture triggers work very well for me.
