PTT Oil & Retail (OR) · 2022 · Mobile · Web · UX/UI Designer
EV Station PluZ
The charging companion for Thailand's biggest fuel network — plan a trip, charge, pay, and review in one app.
“สถานีนี้มีสิ่งอำนวยความสะดวกอะไรบ้าง?
What does this station actually have?
“เครือข่ายครอบคลุมไกลแค่ไหน ก่อนจะกล้าขับทางไกล?
How far does the network reach before I commit to a long drive?
“การจองเวลาชาร์จทำงานยังไง?
How does picking a reservation time actually work?
ch.01 · the problem
Three questions drivers kept asking
Reading the app's support logs and store reviews, the same three worries came up on repeat: what facilities does this station actually have, how far does the network reach before I commit to a long drive, and how does picking a reservation time work? None of these were charging problems — they were information problems the app had been answering in fine print.
fixed before I started
ch.02 · scope
What I designed, what was already fixed
Designed
- Station detail redesign — facilities, scope, and conditions up front
- Reservation time selection flow
- Live charging session UI with stop-charging safeguards
Given
- The existing PluZ app and its live users — this was a redesign, not a new build
- Charging hardware and the PTT Station network — PTT OR
- Brand identity — PTT OR
ch.03 · approach
Conditions in plain language
The redesign promotes station facilities, network scope, and usage conditions to first-class UI — readable before the drive, not discovered at the plug. Reservation time selection became a deliberate step instead of a gotcha, and the live session screen leads with the three numbers that matter: energy, distance gained, and cost.
ch.04 · approach
Decisions, and why
d.01
Promoted facilities, reach, and conditions to first-class UI
drivers decide before the drive, not at the plug
d.02
Made reservation-time selection a deliberate step
buried in fine print, it had read as a gotcha
d.03
Led the live session with energy, distance, and cost
those are the three numbers a driver actually acts on
d.04
Built stop-charging safeguards into the session
an accidental stop is the expensive error to prevent
the reel · every screen, in order
ch.05 · outcome
Where it landed
OR's nationwide charging service
shipped as EV Station PluZ, riding on the PTT Station network — Thailand's biggest fuel retailer
ch.06 · delivered
- Station detail redesign — facilities, scope, and conditions up front
- Reservation time selection flow
- Live charging session UI with stop-charging safeguards
ch.07 · reflection
If I did it again
Prove the fine-print fix worked
Track whether drivers actually stop asking the three questions — support volume on facilities and reservations is the honest before/after I didn't set up.
Test the reservation step with real drivers
Reservation time was the trickiest flow; a small moderated test would have told me sooner whether the new step read as deliberate or just different.
accepted limitationWorking on top of a live app, some patterns had to stay familiar to existing users — not every screen could be redrawn from scratch.
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