SteamDB
A third-party Steam database covering product history, pricing, concurrent players, tags, and store changes.
Why use it
Useful for checking niche size, competitor cadence, and player interest before committing to a concept.
Where it fits
Study the market and the players you want to reach, then turn a loose idea into something you can test.
What to check
It is not a Valve service; estimates and historical signals still need qualitative interpretation.