Issue populating fields on iOS

[KylePyne]

I am having an issue when populating fields from a substr calculation (from a scanned barcode). Everything works properly on Connect, but not on the published survey within the iOS app. The first three fields work fine, the rest do not populate.

Some of these fields are referencing a choice list as it is the only way I have found to display a different value.

For example the first two characters in the barcode are PE which populates "Performance Pipe".

(Having this populate without a select_one list is an entirely other issue)

I have attached my form for reference.