LINKTOAPP( app-id )
app-id - An expression that gives the ID of the target app.
LINKTOAPP() constructs a deep link to the app identified by app-id.
AppSheet does not validate app-id. If invalid (e.g., misspelled, or otherwise refers to a non-existent app), no error will be displayed.
app-id may be of any type, is interpreted as Text, and will be encoded (as with ENCODEURL()) for use in the deep link.
An App value: the constructed deep link.