lwh0630 / SignalScope

# SignalScope
**An Android network-signal inspector built with Flutter and Kotlin.**
SIM and carrier info, LTE / 5G NR cellular signal, Wi-Fi and nearby access points, GNSS satellites, and a TCP / DNS latency test.
简体中文 | English
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> **Core principle: only show values the system actually reports.** There is no random or hard-coded data in real mode. A field the system does not provide is `null` and shown as `--`, never as `0`. No hidden APIs, no reflection, no root.
## Table of Contents
- Features
- Screenshots
- Tech Stack
- Android Compatibility
- Permissions
- Install and Run
- Build from Source
- Project Structure
- Development Status
- Contributing
- License
- Acknowledgements
## Features
| Page | What it shows |
| --- | --- |
| **Overview** | Per-SIM carrier, network type, primary signal and IPv4 / IPv6; Wi-Fi state with IPv4 / IPv6 / MAC; GNSS state; cellular and Wi-Fi trend charts. Tap a card for details. The speed icon at the top right opens the latency test. |
| **Cellular** | Independent state for each SIM (SIM1 / SIM2 switch). SIM, carrier, MCC/MNC, roaming, data state. LTE: RSRP / RSRQ / RSSI / SINR / CQI / TA, PCI, TAC, CI, eNodeB ID, EARFCN, band, bandwidth. NR: SS / CSI RSRP / RSRQ / SINR, PCI, TAC, NCI, NRARFCN, band. NSA / SA detection, neighbor cells, 60 s / 5 min trends. |
| **Wi-Fi** | Current connection (SSID, router MAC, RSSI, frequency, channel, width, link speed, IPv4 / IPv6, device MAC, gateway, DNS, security, standard), nearby access points (band filter, sorting), 2.4 / 5 / 6 GHz channel graph (tap for details), RSSI trend. |
| **GNSS** | Fix status, latitude / longitude, altitude, accuracy, speed, TTFF; visible / used-in-fix / tracked satellite counts; constellation breakdown with country / organization flags; sky plot; C/N0 bar chart grouped by constellation; satellite list; C/N0 and satellite-count trends. While there is no fresh GNSS fix, the position card shows the system's fused / network position (Wi-Fi, cell towers) instead, clearly labelled "not GNSS", and switches back to the GNSS fix automatically once one exists. |
| **Latency test** | DNS time plus TCP-handshake timing (min / avg / max, jitter, loss) against built-in site lists (Mainland China, US / international) and up to 20 custom targets. |
| **Settings** | Theme (dark-first / light / system), language (Chinese / English / system), refresh rate, history window, CSV / JSON export, clear history, permission manager, demo mode, app update, about. **App update**: checks the latest GitHub Release (automatically at launch at most once every 24 hours, switch-off in Settings, or by tapping "Check for updates"), downloads the APK for the device's ABI, verifies its SHA-256 against the release's `SHA256SUMS.txt` and its signing key against the installed app, then opens the system installer. Stable releases only; drafts and pre-releases are ignored. |
Also: multi-SIM support with per-subscription isolation, event-driven sensing