The situation with retail chains is improving thanks to projects such as https://alltheplaces.xyz/ (disclaimer: I'm a contributor) and efforts of some OSM contributors to focus their contributions towards comparing OSM and ATP features to add missing shops, remove closed shops, update opening hours, etc. For one such example, see https://matkoniecz.codeberg.page/improving_openstreetmap_usi... for a tool (created by https://news.ycombinator.com/user?id=matkoniecz) which is used to match and compare OSM and ATP features.

This work has been slow to take off though as the OSM community has traditionally been stuck on time wasting debates about whether opening hours displayed on the wall of a shop are copyrighted (just the raw data, not a photo of their presentation), and debating the merits and pitfalls of armchair mapping vs. on-the-ground mapping. At least these historical roadblocks seem to now be mostly resolved.

For OsmAnd, you might be able to use the OBF import feature (see https://www.osmand.net/docs/user/personal/import-export/) to add the raw ATP dataset, or potentially other open data such as Overture Maps if that is more to your liking. Data is mostly sourced direct from brand websites, APIs, etc (as if you were using a storefinder map on their website).