Functions on inactive screens run each time a variable or field updates.

[Anonymous]

I want to reference them in those other screens functions, but i dont want 3 screens worth of functions running everytime i choose a different variable value on a different screen, its bogging down app functionality. 

Any tips?

[RandyHayes · Accepted solution]

@Anonymous 

PowerApps is Excel!!  It always evaluates formulas you have all the time and on any page (in this case - screen).

Any time you change something that is referenced in a formula, that formula will be re-evaluated.  This is just how it works.

So you have to account for that as you build your app.  Either make your formulas global rather than screen-by-screen, or write your formula to not depend on something that will change elsewhere and not be needed.

There are a lot of "ways" to go about all the above, and it is always very specific to the app and design, so there is no magic "do this - not that" to mention, it is all dependent.

I hope this is helpful for you.

[Anonymous]

Thanks, that was my tentative conclusion, was just hoping it wasn't the case 😅

[RandyHayes]

@Anonymous 

Yes, getting performance clean in PowerApps is a bit of an art.  It really is about keeping in mind that you are writing formulas just like in Excel and not code (which it is not) that would run only when something makes it run.  Keeping that in mind ALL the time is key to being performance aware.