Proj4

proj4 coordinate converter

marco.corvi · com.topodroid.proj4

Not rated yet 1K+ downloads v1.1.35 1.7 MB Android 5.0+ PEGI 3 · Everyone

Download APK 1.7 MB All versions

Signature matches the Google Play version Details

At a glance

Latest version: v1.1.35 (10135)
Updated: Sep 2, 2026 (1 month ago)
APK size: 1.7 MB
Requires: Android 5.0+ (API 21)
CPU support: ARM 32-bit, ARM 64-bit
Category: Tools (app)
Listed since: Feb 16, 2021 (at least)
Permissions: 1 (1 sensitive)
Website: sites.google.com/site/speleoapps/home/proj4
Developer contact: [email protected]
Privacy: Developer's privacy policy

About this APK

Proj4 is an app by marco.corvi in the Tools category, listed since at least February 2021. It includes native code for ARM 32-bit and ARM 64-bit, so it runs on practically every phone.

Since version 1.1.23, the minimum Android version rose from 2.2 to 5.0. It asks for 1 permission, 1 of them sensitive: read shared storage. Compared with version 1.1.23, it adds 1 new permission (“Read shared storage”) and drops 1 (“Modify shared storage”).

What's new in v1.1.35

Simplified the interface of the coordinates conversion for TopoDroid

Description

From the listing uploaded by “appupdater”.

Simple coordinate converter based on the Proj4 library http://http://trac.osgeo.org/proj The basic feature is the coversion of coordinates between two Coordinate Reference Systems. It includes the computation of the current megnetic declination based on WMM data. The coordinates can be imported from MobileTopographer point lists. The point can be visualized on maps/earth. Java wrapper for proj4 by Martin Deruisseaux (2011) http://www.geoapi.org/geoapi-proj4/index.html The app includes a limited number of Coordinate Reference Systems. Custom Coordinate Reference Systems, in proj 4 sytax, can be added to the app. See https://sites.google.com/site/speleoapps/home/proj4 Details and contacts: https://sites.google.com/site/speleoapps/home

Version history

2 versions are listed, going back to v1.1.23. Since v1.1.35 it requires Android 5.0+.

v1.1.35 LATEST Sep 2, 2026 1.7 MB TRUSTED v1.1.23 May 18, 2024 2 MB TRUSTED

All 2 versions

Security & authenticity

Security rating: Trusted

Signing certificate

Signature matches the Google Play version Checked by the source store on Sep 2, 2026.
Certificate issued to “none” This is the certificate of the Google Play version.
Same certificate as the other version checked

Store checks and file details

Developer signature verified Sep 2, 2026
Validated against Google Play Sep 2, 2026
Signed byCN=marco corvi, OU=none, O=none, L=recco, ST=genova, C=it
Signing certificate (SHA-1)DF:C1:71:48:6F:87:A8:C0:BE:E2:1D:F2:7F:B8:F2:4C:77:51:04:FA
File MD5bd4bc92e9a626b9059a9a179de31e9fd
Uploaded by “appupdater” Gold tier · 117,810 followers · uploading since 2020

Scans and ratings come from the source store; the certificate comparisons are AAPKs's own, made from the files' published signatures (1 other version compared). AAPKs doesn't scan files itself — compare the MD5 and signer after downloading.

Permissions (1)

Proj4 requests 1 permission, 1 of them sensitive.

Read shared storage Sensitive android.permission.READ_EXTERNAL_STORAGE

Required hardware & features

Basic touch input android.hardware.faketouch

Proj4 APK: questions and answers

Is there a version of Proj4 for older Android phones?

The current version needs Android 5.0 or later. Version 1.1.23 is the newest listed build that installs on Android 2.2 and later. It is an old build: apps that rely on online services may no longer connect when they are this old. Get version 1.1.23 · All versions

Can I install this APK over the version I already have?

Yes, if your installed copy is older. It is signed like the Google Play version, so Android installs it as an update and keeps your data.

Is the Proj4 APK safe?

No one can promise that a file is safe, but some things can be checked. The source store rates this file Trusted. Its signature matches the Google Play version. It is signed with the same certificate as the other version checked. After downloading, check that the file's MD5 is bd4bc92e9a626b9059a9a179de31e9fd.