Guesstimate / an estimation mobile game
Guesstimate is a game built around estimation. Players compete to get closest to the correct answer on questions that are impossible to know precisely. It's not about what you know, it's about how well you can guess.
process.
identifying the problem
The idea came from watching a TV game show and thinking about how fun it would be to play something similar with friends. A quick App Store search confirmed that this type of game didn't really exist on mobile. There were plenty of trivia and word games, but almost nothing focused on the social experience of estimating together.
solution & plan
My goal was to create something that genuinely brings people together, not a game that disappears into individual screens. To do that, I kept three things at the center of every decision:
- a clean interface that keeps focus on the question,
- rules simple enough to explain in under a minute and
- a structure that scales from a small family gathering to a bigger group without friction.
high fidelity wireframes
onboarding
Guesstimate's onboarding is a 3-step setup designed to get players into a game as fast as possible. Players can sign in with Apple, Google, or email — or skip registration entirely with "Play as guest".
From there, they pick a name and avatar color, set notification preferences, and land straight on the home screen. No unnecessary friction before the fun starts.
two modes
I noticed people play differently depending on their situation, so I designed two modes to reflect that.
"Pass the phone" (2–8 players) works when everyone's in the same room, one device gets passed around and each player types their guess in secret.
"Every phone" (2–20 players) lets everyone join on their own device via QR code or link, so the game can scale to bigger groups or different locations. Scores carry over if you switch modes mid-session.
host mode
When setting up a game, the creator decides who hosts. Choosing "I'll host" means you read each question aloud and keep the pace, but you don't get to answer. Choosing "Another player hosts" passes the role to someone already in the waiting room.
Hosting can be handed off anytime before the game starts, which keeps things flexible as the group settles in.
non creator-non host
Players join by entering a 6-character game code or scanning the host's QR. A quick connection handshake confirms they're in, then drops them into the waiting room, where they can see who else has joined and who's hosting.
Once the host starts the game, players get a countdown, see the question, and submit their guess before time runs out. After everyone locks in, the host reveals the answer.
what I've learned.
I learned to create color styles, components and variants, rather than designing screens in isolation
Dark mode was new to me. I learned that depth comes from layering surfaces, not adding shadows.
Designing a game taught me to think in states, before, during, and after every player action, across multiple roles.