# SliP Symbolic Calculator — A programmable calculator

> A programmable calculator (iPhone/iPad app by Satoru Ogura.)

- Source: https://appshunter.io/ios/app/slip-symbolic-calculator/id1097457043 (this page in markdown: same URL + `.md`)
- Developer: [Satoru Ogura](https://appshunter.io/developer/297709042)
- Category: Utilities, Developer Tools
- Price: Free
- Age rating: 4+
- Requires: iOS 17.0 · 1 MB
- Languages: American English, Japanese
- Released: 2016-03-30
- Data updated: 2026-08-25
- User reviews in markdown: https://appshunter.io/ios/app/slip-symbolic-calculator/id1097457043/reviews.md

## What is SliP Symbolic Calculator?

SliP is a symbolic calculator you can program.

Start with it as a calculator: write a line, press return, and the answer is there. A name made on one line is there on the next, so 'r = 2 and then 2πr does what you would expect. What you write stays as a history you can correct and read again.

The same thing is a language. Switch to programming mode and the text rewrites itself into toplevel forms; switch back and it returns to a line at a time. Two views of one thing.

WRITTEN THE WAY MATHEMATICS IS WRITTEN

π and × and ÷, the set operators ∈ ∋ ∩ ∪, the truth values ⊤ ⊥, and Greek letters as names. None of that is on a keyboard, so all of it is on the keypad: forty-seven operators, twenty-four functions, forty-eight Greek letters and the Latin alphabet. On iPhone the system keyboard never appears, because everything the language is written in is already in front of you.

THE SCREEN

The keypad sits beside the work where there is width for it and under the work where there is not. Turning a phone over is the same question as picking up an iPad, and it has the same answer.

DOCUMENTS

A document is an ordinary text file. A first line of //SLIP opens it as a program; without one it opens as a calculator's history. Opening it runs it, so you start where you left off.

ALSO

- macOS and iOS run the same C++ engine
- The same language runs in a browser at https://slip.828.tokyo
- No advertising, no analytics, no account, no network. Everything is evaluated on your device

The complete language reference is at https://slip.828.tokyo/SPEC.html


## Version history (last 3 releases)

### 2.3.0 — 2026-08-20

The calculator works the way a calculator does.

- Answers at the top, the history under them, one line to write in at the bottom. Return puts that line into the history and its answer above; a name made on one line is there on the next ('r = 2, then 2πr).
- The history is editable, and RUN reads the whole of it again from the start.
- Opening a document runs it, so what is on screen when it opens is what the document says.
- A file now says how it is meant to be read: a first line of //SLIP opens it in programming mode. Changing mode rewrites the text into what the other mode would have written.
- A new document is empty.

The keypad has been rebuilt.

- The same seven-by-four block on every host, carrying delete and run as keys.
- The keypad sits beside the display where there is width for it and under the display where there is not, so turning a phone over is the same question as picking up an iPad.
- The iPhone no longer raises the system keyboard. Everything the language is written in is on the panel, and the keyboard's only contribution was to cover it.
- Two keys that put in characters the reader has never heard of are gone.

RUN is one reading of the whole of what is written, from the start, always. The Keep session switch bought less than the second rule it cost.

The language itself is unchanged.

### 2.2.0 — 2026-08-17

Fixed the sign of negated constants.
A named constant with a minus sign in front of it was computed as though
it were positive. -π × 2 was treated as +π × 2, and -π + 1 as π + 1. The
screen showed (-π) correctly, which is what made it hard to see.
Negative numbers were never affected: -3 and -0.5 were always right. Only
the named constants were, namely pi, Euler's number, infinity, gamma,
phi, log2e, log10e, ln2 and ln10.
If you have used a negated constant in a calculation, its result changes
with this version.
Engine updated to 2.2.0.

### 1.0 — 2026-08-05

No release notes.

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-25.*