Hardware wallet simulator: the phone app a mockup can draw, and the device it cannot

A hardware wallet has a stamp-sized display, a couple of buttons and a chip that signs. A mockup of a phone screen reproduces none of them. Fortunately the phone app is often the thing people were looking for.

Published: 19 September 2026 · Last reviewed: 25 September 2026

A chip, a button and a small window

Picture the device on a desk. It has a screen about the size of a postage stamp, a pair of buttons, and a chip inside that holds the key and never lets it out. Everything that makes a hardware wallet a hardware wallet lives in those three things. A picture of a phone screen contains none of them.

That explains why the search term is slippery. Two unrelated products hide behind "hardware wallet simulator":

• An emulator. The device firmware compiled for a desktop, showing the tiny display in a window, so developers can test a build without flashing hardware. These come from the device projects themselves and are made for people writing firmware.
• A mockup of the companion app. The phone app that pairs with the device over USB or Bluetooth and lists accounts, balances and tokens. This is an ordinary mobile interface.

Most people typing the phrase want the second and have never heard of the first.

The same word, two very different canvases

Common device displays measure 128 by 64 pixels and are monochrome, while colour panels run at roughly 240 by 240. A screenshot from a phone is 1179 by 2556 on an iPhone 14 Pro. The gap is not one of scale. It is a difference in kind.

Consider an address of 42 characters on a 128-pixel-wide display. It will not fit on one line. Firmware either breaks it across pages or shows the beginning and the end with the middle elided, and the typeface is picked so that an eight cannot be mistaken for a B. An app layout carries none of those constraints, so a phone design shrunk into a device frame looks wrong immediately.

Three things no drawing can supply

• The signature. The key stays in a chip that does not release it. The device signs, and the computer never sees the secret. A drawing has no chip.
• The press. Security comes from a button pushed while looking at a screen the host machine cannot alter. A rendered image has no press behind it.
• Seed creation and backup. Entropy, word lists, verification prompts. Our tool never asks for a seed phrase and has nowhere to type one.

This is also why a mockup is the wrong thing to hold up as evidence. An image of an approval, however tidy, shows that someone drew it. It is a mockup, never a proof of funds.

What Flexdger Wallet does draw

One thing: the application screen. You choose tokens, quantities and unit prices, the accent colour, the avatar and the account name, and live market prices move in the fiat column. The screen opens on your phone at its own address, ready for a pitch, a deck slide, a tutorial frame or a demo of software with no data yet.

For a device product, that covers the companion app, which is where most of the design work sits. It is a mockup and is presented as one: it holds nothing, connects to no chain and proves nothing about any balance.

If you must document the device itself

Handle the three parts separately.

1. Physical steps. Photograph the device on a plain surface, with the display bright enough to survive the exposure.
2. Exact firmware wording. Run the project's own emulator.
3. A clean asset. Redraw the small screen by hand. At that size it is an afternoon in a vector editor, not a rendering problem.

Then compose the phone side on its own. It is a different screen.

Searching for a Ledger larp wallet? A hardware wallet screen in a video explains what a screen can and cannot show.