The Wikipedia Android app shows item descriptions from Wikidata. Reading an article in Alemannic, it shows correctly the description with language code "gsw" if available.
However, when adding a description, it is saved on Wikidata under the wrong language code "als" (example edit).
When editing an existing "gsw" description, the "gsw" description is untouched and a new description under "als" is added (example edit).