Didarul Islam
BackpackLink
Case study — solo founder
Product design & development

Land. Scan.
You’re online.

BackpackLink is affordable, instant eSIM data for backpackers, students and digital nomads — researched, designed, and built solo, from the first wireframe to the App Store listing.

214+ countries Instant QR delivery No roaming shock
RoleFounder · Designer · Developer
PlatformiOS · Mobile app
ScopeResearch → UI → Build → Ship
BackpackLink plan details screen
BackpackLink destination search home screen
The problem

Roaming still punishes the way people actually travel.

  • Airport SIM kiosks and plastic SIM swapping between every border
  • Daily roaming fees ($10–15) that quietly outprice the trip itself
  • Plans sized for a 3-day business trip, not a 3-month loop through a region
  • The travelers moving the most — backpackers, students, nomads — are priced like occasional flyers

Travelers don’t want a phone plan. They want data that works the moment they land — without the markup.

Who it’s for

Built for people who move, not just visit.

Backpackers Students abroad Digital nomads
  • ×Roaming shock the moment you land at a new border
  • ×A physical SIM to track down, buy, and swap in every country
  • ×Plans sized for a business trip, not a six-month loop
  • No roaming shock — pricing is visible before you ever pay
  • No SIM swapping — one QR code, activated on arrival
  • No complicated plans — coverage across 214+ countries
How it was made

One person, every layer of the product.

Strategy

Product vision & positioning

Defined who BackpackLink is for and what it refuses to be — another roaming plan.

Design

End-to-end UI/UX

Flows, wireframes, and a full interface system, built for one-handed use on the move.

Engineering

Full-stack development

Shipped the product end to end — destination search through checkout and delivery.

Go-to-market

Pricing & launch

Researched carrier rates and traveler budgets to price every plan.

“I designed it, built it, and shipped it. There was no one else to hand it off to — every decision, and every bug, was mine.”

Research

What actually matters to a traveler with a backpack.

01

Surprise bills are the real enemy

Roaming shock — not price alone — is what travelers remember, and what they warn other travelers about.

02

Coverage should start on arrival

The expectation is simple: data activates the moment a phone finds a local network, not before.

03

Price sensitivity runs high

Backpackers and students plan around a fixed daily budget — a plan has to fit the trip, not the other way around.

04

Clarity is the trust signal

A visible network list and an upfront price, shown before checkout, do more work than any badge or guarantee.

Inside the app

Seven screens, one uninterrupted trip.

From the first search to the account that manages every eSIM — every screen shown here is the live product.

BackpackLink app screen
Tap a step or swipe the phone to explore
Explore Search any of 214+ destinations and see coverage before you commit.
Process

From a blank page to a shippable product.

1

Flows & IA

Mapped the shortest path from “where am I going” to “I’m online.”

2

Wireframes

Low-fidelity screens to pressure-test the checkout and search flow.

3

High-fidelity UI

Applied the visual language — teal, cream, coral — across every screen.

4

Design system

Componentized cards, chips, and buttons for a consistent, buildable UI.

5

Build & ship

Wired the real thing: search, plans, checkout, delivery, accounts.

Where it landed

A working product, not just a prototype.

214+
Countries with coverage
$1.34
Lowest plan price tested (Japan, 1GB / 3 days)
1
Person across strategy, design & code
Instant
QR delivery straight after checkout

BackpackLink shipped as a complete, working product — search, transparent plan details, checkout, instant delivery, and account management — designed and engineered end to end by one person, with no team to hand work off to.

Looking back

What building it solo actually taught me.

01

Pricing transparency isn’t a feature — it’s the pitch

It deserved to be designed first, not bolted on before checkout. Showing the network list and price upfront became the product’s clearest trust signal.

02

Building alone forces ruthless prioritization

With no team to absorb scope, every screen had to earn its place before it got built.

03

Trust lives in the details

A visible carrier and network list did more work than any guarantee badge could have.

Next

Deepen the community layer

Travelers trust other travelers more than any coverage map — that layer is still early.

Case study — end

Built by one person, for people who move light.

BackpackLink is a solo-built product — every screen shown here is live, working software. Reach out to talk through the process, the product, or what’s next.