Flipper API Caller

August 26, 2026 · View on GitHub

A Flipper Zero application for saving API calls and sending them through a ESP32 FlipperHTTP-compatible Wi-Fi board. Call scheduling, .json import and per-call run history are on the roadmap.

Features

Connection (via FlipperHTTP board)

Wi-Fi scan with live, non-blocking updates (auto-refresh every 8 s)
Saved networks history (SSID + password, quick reconnect)
Connect / disconnect with status feedback

Saved API calls

Add/edit form: URL, HTTP/HTTPS protocol, method (GET/POST/PUT/DELETE/PATCH/HEAD), query, headers, body
Automatic http:// / https:// scheme normalization
Call list persisted on storage (up to 16 entries)

Execution and logging

Non-blocking request execution, 30 s timeout, distinct error messages
Full response body view (up to 32 KB) in a custom scrollable view
Debug log at /data/debug.log (auto-truncated at 32 KB)

Supported hardware

The app only speaks the FlipperHTTP text protocol over the Flipper UART (TX pin 13, RX pin 14, 3v3 pin 9, GND pin 11), so it is board-agnostic:

ESP32 (WROOM/S2) running FlipperHTTP v2.2.0
Power: the official Wi-Fi Devboard runs from the Flipper 3v3 rail; bare devkits are best powered via USB.

Building

Builds with uFBT.

ufbt build    # builds dist/api_caller.fap
ufbt format   # clang-format (run before lint)
ufbt lint     # code style checks
ufbt launch   # deploy and run on a connected Flipper

Project structure

.
├── application.fam            # Application manifest
├── CHANGELOG.md
├── README.md
├── images/                    # Icon assets
└── src/
    ├── api_caller.c/h         # Entry point: AppContext, SceneManager, ViewDispatcher
    ├── api/
    │   ├── flipper_http.c/h   # Vendored FlipperHTTP C SDK (v2.2.0)
    │   └── call_runner.c/h    # Non-blocking HTTP request execution
    ├── scenes/                # scene_main, scene_wifi_*, scene_call_*
    ├── wifi/
    │   └── wifi_manager.c/h   # FlipperHTTP wrapper (UART, scan, connect, status)
    └── utils/
        ├── api_text_input.c/h # Extended keyboard (UART Terminal, MIT)
        ├── wifi_history.c/h   # Saved networks (FlipperFormat)
        ├── call_history.c/h   # Saved API calls (FlipperFormat)
        ├── long_text_view.c/h # Custom scrollable text view
        └── logger.c/h         # debug.log writer

Roadmap

App scaffold (AppContext, SceneManager + ViewDispatcher), main menu and scene navigation.

0.1.1 - Wi-Fi connection ✔️

Vendored FlipperHTTP C SDK, asynchronous AP scan with live updates, SSID/password input, saved networks history.

0.1.2 - Saved calls ✔️

CallEntry data model, "Add call" form, call list with edit/delete, storage persistence.

0.1.3 - Execution and logging ✔️

FlipperHTTP request execution (GET/POST/PUT/PATCH/DELETE, HEAD mapped to GET), response display, debug.log logging, error and timeout handling.

0.1.4 - Optimization and UI

Icons and assets
Extended keyboard with symbols (based on UART Terminal, MIT)
Stack profiling (top, free)
Loaders and user feedback where needed
Hardware testing, documentation and release

v0.2+ (planned)

Call scheduling (in-app scheduler / ESP32 autonomous scheduler / hybrid - TBD)
Import of calls and call lists from .json
Connection details screen
Auto-connect to the first available saved SSID (continuous background scan; no scan without a saved SSID; stops after connecting)
In-app run history (Call list → Run list) and per-call .log export
n8n / Activepieces nodes (text, number, bool)

Documentation

User guide: requirements, FlipperHTTP firmware setup and how to use the app
Developer guide: toolchain, project conventions, protocol notes and release workflow

Resources

Acknowledgments

Extended keyboard (planned for 0.1.5): based on the custom keyboard of UART Terminal by cool4uma (MIT license) — symbols page with long-press characters, derived from the stock Flipper text input.