Can you please let me know if powerapps is suitable for multi screen and multi list related customizations.
Like 4 lists associated with one main list that will hold key metadata. And in main list, form is customizated using power app and it will have multi screens from the dependant 4 lists. Overall, all screens together might have 400 controls in the worst case.
Assuming I understand right, I'd say the answer is yes.
I have an app that I am currently building where I have daisy chained lists together using the first list's SharePoint ID as the unique identifier in the other lists so a record will link across the multiple lists.
When I create a new record on the first screen, it populates an ID field in the other lists which then allows me to edit and save (I do not apply any conditions to my SharePoint fields as PowerApps will control that).
When I go to edit the record, I have it search for the ID of record and it pulls things up seemlessly.