Unable to establish a secure connection to Square - Mobile Payment SDK

Questions
1

Hey!

I’m currently working on my personal project for iPadOS, involving Mobile Payments SDK. When testing my app, I’ve noticed my square reader 2nd gen, rejected to work via bluetooth, showing an error “Unable to establish a secure connection to Square”. (Square account is verified through OAuth) This message never appeared when reader was connected to square stand (1st get lightning version) over usb. Somehow, after couple of weeks of testing, the reader now refuses to take payments even over usb (same with the DonutCounter sample app). My question is, is this caused by me using a Free Apple developer account for signing the app? Since this is just a personal app, I was hoping to use it without a paid developer account for now.

Thank you so much.

2

:waving_hand: I’m Square Dev AI, here to help answer your question!
Based on the information you’ve provided, the following documentation will help answer your question:

https://developer.squareup.com/docs/reader-sdk/build-on-ios

Additional Documentation

Tap to Pay on iPhone
Offline Payments
https://developer.squareup.com/docs/reader-sdk/cookbook/contactless-reader

If this documentation helped you find a solution, please check the box indicating that this reply solves the problem.
Otherwise one of our Developer Advocates will provide additional assistance shortly.

3

Still need help. I’ve purchased an Apple Developer account, signed with the new signature after updating this on square dev portal… but still Failing to establish connection to Square, for a couple hours, after which both stand and reader magically connect. Tried on multiple iPads, all the same issue - including DonutCounter app

4

@RichardR I don’t believe this is an issue with using a free vs paid Apple developer account. If the issue was with your application signature, that would manifest as consistent issues taking payments, not as a connection issue that seemingly resolves itself after a few hours.

Do you mind providing the following?

  • Your application ID (not your access token)
  • The Location ID you’re having issues with
  • A timestamp of one example of this issue occurring (date, time, timezone)
5

Hey Josh!

Thanks for the quick reply.

Application ID: sq0idp-6AUlVUtAZT0rPJoUOp4dtQ
Location ID: LAN92EDH3GGSD

Example failure timestamp:
2026-04-28, 21:18:33 UTC (≈22:18 BST)

6

@RichardR Thanks for sending that over! What version of Mobile Payments SDK are you using?