Is there a primary root cause when you see this message?
One of my customers was experiencing this error a lot, mostly using the app using on newish iPads. On computers it worked just fine. The doc is not specially big, around 22k rows in 40 tables. Changing to the Webapp solved the issues.
I opened a new doc to test a layout today. It has one table with 8 lines of fake name entries. It has 4 columns (fake names, check box column, number entry, number entry) and I got the same error. I don’t use the app much but wanted to see if that app would be good for collecting event data with phones or iPads.
welcome to the community! 
for iPads, its better to use coda in safari or on a web browser app.
there are a few quirks to it as compared to using coda on a web browser on a computer but in general it has almost full functionality (and similar performance).
Namely, scrolling to find a page in menu side bar reorganized them instead (but maybe thats user fault lol) and it is more cumbersome to build (edit formulas etc).
But definitely can vouch for ipad / safari setup as a few months ago my laptop croaked itself whilst on holidays and on my ipad pro i was able to build mckinsey style charts & dashboards for one client and a complicated Projects and Tasks (Work Breakdown Structure) with lots of conditionals etc for another client. Those were fun times 
as for the mobile app.. i would say it is not very reliable / usable at the moment but am under the impression that its going through a revamp??
there’s an upcoming roundtable for this topic (see below) and maybe we will get more definitive answers then.
hope this helps!
cheers!
Mel
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