Mattel163: Phase 10 Mobile

How to build a mobile game from zero to ONE and grow its loyal fanbase

Project
Phase 10 Mobile Game

Role
Art Direction, Interaction Design and UX Research

Team
Senior UI Designers (2), 2D Animator and Concept Artist

Date
October 2018-March 2020

problem

Phase 10, a rummy-style card game with a dedicated but niche fanbase, faced the challenge of expanding its appeal without alienating its core players—primarily women aged 20 to 40 who enjoy casual strategy games. The objective was to create a mobile version that stayed authentic to the game’s roots while attracting new players, especially from the UNO fanbase.

Goals

  1. Player Retention & New Player Appeal:

    • Maintain loyalty among existing Phase 10 players.

    • Create an intuitive onboarding experience to attract and retain new players.

  2. Play Anytime, Anywhere:

    • Design for short, flexible play sessions (3–5 minutes).

    • Implement offline play with an arcade mode.

    • Optimize for portrait orientation to support one-handed gameplay.

  3. Continuous Usability Testing:

    • Conduct regular player tests at critical development milestones.

    • Use player insights to inform design iterations and improve gameplay experiences.

PROCESS

Team Structure & Collaboration:

Built and led a lean, agile team, overseeing art direction, hiring, and UX.

Recruited an animator, UI designer, and concept artist with skills to integrate art directly into Unity for seamless collaboration with engineers.

Managed cross-continental collaboration between teams in Los Angeles and Hangzhou, using InVision for clear feedback and interactive prototypes.

Design & Development:

Partnered with the Mattel brand team to finalize a style guide that ensured visual consistency between the mobile game and the physical card game.

Created wireframes to validate key features, including portrait orientation for mobile playability.

Prioritized social features based on player research, emphasizing private games with family and friends over random online matches

Player Research & Usability Testing:

Ran usability tests (RITE) with real players to identify pain points and track improvements across sprints

DESIGN

Onboarding Experience:

Developed a comprehensive tutorial that clearly explained game objectives, rules, and terminology. However, feedback indicated experienced players preferred an option to skip tutorials.

Art Direction:

  • Led the creation of a clean, simple, and relaxing art style, aligned with the expectations of casual game players.

  • The final design was visually soothing, making long play sessions easy on the eyes.

Social Features:

  • Focused on fostering familiar, comfortable multiplayer experiences by enabling private games with friends and family.

  • Integrated leaderboards to add a light competitive edge without overwhelming casual players.

Social Interactions

Players can start a game with their friends by inviting them to a game room

Players can start a game with their friends by inviting them to a game room

The host player can do three actions: 1) Select number of phases 2) Invite Friends 3) Emote with quick phrases and emojis

The host player can do three actions:
1) Select number of phases
2) Invite Friends
3) Emote with quick phrases and emojis

Tapping the ‘Edit’ pencil icon allows players to change the number of phases. We wanted to limit the number of phases allowed since the full ten phrases between three players would be difficult to complete.

Tapping the ‘Edit’ pencil icon allows players to change the number of phases. We wanted to limit the number of phases allowed since the full ten phrases between three players would be difficult to complete.

Tapping on the ‘Add Friend’ icon at the top will prompt ‘Invite Friends’ popup. Inviting online friends would appear first in the list. Offline friends will receive a server-side push notification asking them to join the game.

Tapping on the ‘Add Friend’ icon at the top will prompt ‘Invite Friends’ popup. Inviting online friends would appear first in the list.
Offline friends will receive a server-side push notification asking them to join the game.

Invited friends would receive a drop down notification to ask them to join. If they miss it, the message will be in their inbox.

Invited friends would receive a drop down notification to ask them to join. If they miss it, the message will be in their inbox.

Once the invited friend joins, they will need to wait for the host to start the game. Meanwhile they can chat with other players.

Once the invited friend joins, they will need to wait for the host to start the game. Meanwhile they can chat with other players.

Outcomes

Retention:

8 out of 10 players in post-launch tests played at least 1–2 hours per day, despite challenging levels. Players leveled up quickly, indicating strong engagement, overall comprehension of game rules and finding the fun in the game.

Production Output

With a clean, simple art style based on a 2D pipeline, the team was able to stay small while content output was high with new skins, worlds, and avatars. The "World Tour" feature introduced new events, challenges, and rewards, keeping gameplay fresh. The game launched in June 2019 after six months in development.

Successful Product Impact:

The mobile app attracted a substantial global audience, enabling active online multiplayer experiences. In 2022, the "World Tour" highlighted Phase 10’s history, appealing to both new and veteran players. From 2018-2022, the game remained one of the Top 10 card games in the Apple’s App store.