In-App purchase transaction fails with SKErrorPaymentCancelled in sandbox mode

Question

Context

• Products load correctly via SKProductRequest
• Test users setup via itunes connect and verified
• Logged out from my "normal user" account on the device
• Logged in as test user on the device

Problem

• The payment transaction fails with SKErrorPaymentCancelled without any action from the user
• The app is redirected to the iTunes Store and keeps asking for the user credentials

Answer 1

The problem is that I was logging the test user by using the Settings --> iTunes & App Store --> Apple ID.

This process seems to "convert" the test user into a "real user". In fact, you get asked for credit card info and such, as would be expected for a "real user".

The solution is:

• create a new test user
• ensure that no user is logged in the Settings --> iTunes & App Store --> Apple ID
• test the purchase path in your app
• when asked for user credentials, use the newly created user credentials

I hope this saves you time.