Install Arc Pro
Property inspection app for Android
File: arcpro-v1.9.1.apk · Version 1.9.1
This is the official Arc Pro app from Four Site. You may see a warning during installation because the app isn't from the Google Play Store — this is normal. Follow the steps below to install safely.
Download the app
Tap the Download Arc Pro APK button above. The file will save to your phone — usually in the Downloads folder.
Allow the installation
When you tap the downloaded file, Android may block the install. You'll see a prompt — just tap Settings on that prompt, then enable Allow from this source.
If you don't see a prompt, go to your browser's app settings:
Settings → Apps → Chrome (or your browser) → Install unknown apps → toggle ON
Open the downloaded file
Open your Downloads folder and tap arcpro-v1.9.1.apk.
Or tap the download notification that appeared in your status bar.
Confirm installation
Review the permissions the app needs, then tap Install.
If you see a warning like "This type of file can harm your device", tap Install anyway. This is a standard Android warning for any app outside the Play Store.
Open & sign in
Tap Open when installation finishes. Sign in with your Arc Pro credentials — the same ones you use on the web.
Security note: After installing, you can turn off "Install unknown apps" permission again in Settings. The app will continue to work normally.
Common Questions
Is this app safe to install?
Yes. This APK is the same app that's pending review on the Google Play Store. It's built and digitally signed by Four Site. Android will verify the signature matches the developer certificate before installing.
Why isn't it on the Play Store yet?
Arc Pro is currently going through Google's review process, which can take several weeks. In the meantime, you can install directly using this APK — it's the exact same app.
Will I get Play Store updates later?
Once Arc Pro is approved on the Play Store, you'll be able to update through the Store like any other app. We'll also notify you of any critical updates in the meantime.
I'm getting "Install blocked" or "For your security"
This is normal. Tap Settings on the popup, enable Allow from this source, then go back and tap Install. Alternatively: Settings → Apps → [your browser] → Install unknown apps → toggle ON.
What permissions does the app need?
Arc Pro needs Camera (to take inspection photos), Location (to tag inspection sites), and Storage (to save photos and offline data). These are the same permissions the Play Store version will request.
I need help
Contact our support team at support@four-site.com and we'll get you sorted.
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