POS API Error on Android since 7.22 update

Questions
1

Hello,

Since the Square POS App update rolled out, we’re seeing the following error on multiple users’ devices when trying to open the Square POS App.

Unexpected developer error

Point of Sale API must be started with startActivityForResult) in the same task. It looks like the caller either used startActivity) or used startActivityForResult) from a finished activity or with the FLAG_ACTIVITY_NEW_TASK flag.

Our implementation is in line with the documentation ( Build on Mobile Web ), has worked flawlessly since April 2025 and we haven’t updated any code recently. We are using the following hardware and software versions for testing and can reproduce the error:

Square POS App: Version 7.22.1sw
Chrome: 152.0.7977.64
Android: 16 (Build BP2A.250605.031.A3.X210XXSCEZG6)
Hardware: Galaxy Tab A9+ SM-X210

Our web app is running in the browser, not as a PWA, and we’ve even tested by removing all JS and using only a simple HTML anchor to open the Square app, but we’re still getting the same error. This is the request URL structure we’re using:

intent:#Intent;action=com.squareup.pos.action.CHARGE;package=com.squareup;S.com.squareup.pos.WEB_CALLBACK_URI=https%3A%2F%2Fexample.com%2Fsquare-callback;S.com.squareup.pos.CLIENT_ID=xxxxxxxx;S.com.squareup.pos.API_VERSION=v2.0;i.com.squareup.pos.TOTAL_AMOUNT=2500;S.com.squareup.pos.CURRENCY_CODE=GBP;S.com.squareup.pos.TENDER_TYPES=com.squareup.pos.TENDER_CARD;S.com.squareup.pos.NOTE=notes;S.com.squareup.pos.REQUEST_METADATA=xxxxxxxxx;end

Again, this hasn’t been update at our end for a long time. It’s only started causing issues with the latest update.

Is anyone else getting this? Please help, Square!

Thanks,

James

3

@jimmitch Your implementation and intent URL are correct, and nothing on your side broke. The trigger was a change in Chrome 152: it stopped passing along the browser identity extra that POS used to recognize a request as coming from a mobile web page. Without it, POS treated your web request as an incorrectly launched native one, which is where the startActivityForResult error comes from.

POS 7.23.1 and later handle web requests without relying on that browser hint. Please update your POS app and let us know if you continue to see the error!