# Look4Sat

> See when a satellite passes overhead — An Android satellite tracker that works out when the next pass crosses your sky, and where to look.

- Page: https://tesign.com/en/item/look4sat/
- JSON: https://tesign.com/en/item/look4sat/index.json
- Korean Markdown: https://tesign.com/item/look4sat/index.md
- Generated: 2026-09-19 23:10 UTC

## RANKS

- SCIENCE #4 (As of 2026-09-19 18:00 UTC)

## Numbers

- 1,491 stars — checked on GitHub 2026-09-19 22:57 UTC
- 7-day +6 observed via GH Archive (as of 2026-09-19 18:00 UTC)
- Star total = the value last checked on GitHub (stars_checked_at) + increases observed via GH Archive since. The 24h · 7d · 30d gains are GH Archive hourly events summed to the reference time (as_of). No score of ours.

## AT A GLANCE

- LICENSE: GPL-3.0 (copyleft) — https://spdx.org/licenses/GPL-3.0.html
- USAGE: Use freely. Release your source if you redistribute (copyleft).
- OPEN SOURCE: YES
- LANGUAGE: Kotlin
- PLATFORM: android
- CATEGORY: SCIENCE
- Tags: 위성 · 아마추어 무선 · 안드로이드 · 오프라인
- How to start: Install to use
- SOURCES: GitHub https://github.com/rt-bishop/look4sat
- INSTALL: https://play.google.com/store/apps/details?id=com.rtbishop.look4sat

## ACTIVITY

- Last commit: 2026-09-19 10:35 UTC
- Latest release: v4.4.7 (2026-09-13)
- Contributors: 32
- Open issues (incl. PRs): 37
- Made by: an individual
- Checked on GitHub: 2026-09-19 22:57 UTC

## TESIGN TAKE

One map screen carries the satellite’s position along with azimuth, elevation and distance — exactly what you need to point an antenna.

## WHY IT MATTERS

To work a satellite on the radio, or just to see the ISS, you need to know when it passes and where to look. Look4Sat computes passes for more than 9,000 satellites from Celestrak and SatNOGS data, relative to your own position, and the maths runs offline — useful in a field with no signal.

## BUILD FROM THIS

- Kotlin and Jetpack Compose. There is a satellite list, upcoming passes, a polar radar view and a map, searchable by name or NORAD catalogue number. It predicts up to ten days ahead, shows pass progress with transceiver details, and accepts custom TLE files. It is ad-free and says it always will be.

## WHO IT'S FOR

- Radio amateurs, anyone trying to spot the ISS with the naked eye, and astronomy clubs.

## START IN 5 MINUTES

```
# Install from Google Play, then set your station position in Settings — the predictions depend on it.
```

## CAVEATS

- Android only. A weekly TLE refresh is recommended for reliable predictions, and results are meaningless until you set your position. GPL-3.0: a modified build must be released under the same terms.

## RECEIPT

- FIRST SEEN BY TESIGN: 2026-09-17 06:48 UTC
- AT SOURCE: 2019-10-13 20:04 UTC
- KEPT: 2026-09-19 22:45 UTC
- Published on TESIGN: 2026-09-19 22:45 UTC
- Text last updated: 2026-09-19 23:10 UTC

## How to read this

- This file was produced by the same build, from the same data, as the tesign.com item page. The text is editorial; the numbers are stored observations.
- null in the JSON means not observed — never zero. The Markdown writes [unconfirmed] for it.
- Star total = the value last checked on GitHub (stars_checked_at) + increases observed via GH Archive since. The 24h · 7d · 30d gains are GH Archive hourly events summed to the reference time (as_of). No score of ours.
- A summary, not legal advice.

[Image] https://tesign.com/img/look4sat-3bbcb7fe99.png