I thought the write-up was worth sharing, the dev talks a bit about the process. The app itself looked free and it's labeled as not collecting any data, so I didn't think much of it
Although if there ARE concerns I'm happy to take it down
You can just use Sky Map and search for Sagittarius.
What you actually want to search for is Sagittarius A*, but Sky Map doesn't have that, so the Sagittarius constellation is close enough to give you the general direction.