I have about 15 Apps connecting to one master’s google sheet - total records don’t exceed 400. I have noticed there is a lag when navigating and working with their template editors. About 1-second pause between my clicks (to either add a new line, move things around or editing text fields, etc.). However, when using a single App connecting to its own google sheet with records less than 100, everything works quick and snappy. Any pointers!
I guess this overload is about the IMPORTRANGE formulas. Any kind of formula we use in google sheets can have a delay for secs in the app. I imagine this reflects in your app being almost 100% of the data from formulas
But I am not using IMPORTRANGE any where !