Quick answer
The developer estimates 10–15 hours for We Were Here Tomorrow’s main adventure. Treat that as a planning range, rather than a timer every pair will match.
What changes your playtime?
Your pace depends on solving the puzzles together, comparing clues and exploring rooms. A recorded playthrough’s runtime is not a reliable estimate for a first-time pair: players may already know a solution or move through dialogue and exploration differently.
Plan more than one session
Set aside several sessions and agree on convenient stopping points. If you need help at a particular device, use the chapter and puzzle directory to find the matching guide.
Replaying from the other perspective and chasing collectibles or achievements adds separate goals. The 10–15-hour estimate should not be read as a completionist or all-trophies time.