Audiobus: Use your music apps together.
What is Audiobus? — Audiobus is an award-winning music app for iPhone and iPad which lets you use your other music apps together. Chain effects on your favourite synth, run the output of apps or Audio Units into an app like GarageBand or Loopy, or select a different audio interface output for each app. Route MIDI between apps — drive a synth from a MIDI sequencer, or add an arpeggiator to your MIDI keyboard — or sync with your external MIDI gear. And control your entire setup from a MIDI controller.
Download on the App StoreAudiobus is the app that makes the rest of your setup better.
Living Paint is a hidden gem!
I discovered this app by the dev of Spatializer @quantovox called Living Paint.
I happen to have the Premium IAP for this app, but it may or may not continue to be developed. The dev is thinking of creating a whole new one.
That said... this app is free and it's a lot deeper than it appears on the surface. I think it's worth the IAP even if he doesn't update this version any more. It works perfectly on my iPad 10.5 Pro running iOS14.7.1
As it was originally released in 2015 and never got an update, it runs surprisingly well. No hiccups or anything. Very stable.
You can use the iPad's screen recording but there's this little triangle bottom right that shows up. I get around this by cropping it to 16:9.
Anyway... it's great for making abstract backgrounds that you could use in VS, etc.
I was going to keep this little forgotten/secret gem to myself 
but I'd love to see the dev continue developing it... or a brand new one. It's really pretty unique actually, and worth the IAP for Premium. You can use the majority of the app for free though.
It's a small file size too. Download and give it a try! It seems a bit basic at first... but dig into the settings and swipe over the brushes for a lot more. At first I thought it was just the few that you see when you select brushes... until I realized you could swipe over and reveal A LOT more.
Worth checking out!
Comments
FYI on In-App Purchases:
1. Premium Pass $2.99 (I'm assuming this IAP provides the following 2 for a $1 discount)
2. Brush Pack $1.99
3. Canvas Animator Pro $1.99
It would be nice to encourage this team to develop more IOS apps and make friends here. I suspect we own some of their code in other products where they provided DSP
code... I suspect they are contractually limited in disclosing more details. But I can see from Spatializer that they have deep mathematical skills and can also craft a nice UI.
Very odd timing, I just picked this up out of the blue and ended up grabbing the IAP a few days ago as well. Its a lot of fun. Not gonna lie, kind of stoked to hear they may be making a new one as well!
Definitely looking into this. I’m a helpless VS addict as some might know. Anything useful for background material gets my attention quickly!
Nice find. Thank you.