I detected a possible bug during development that the default mail app is not detected by apps when the Apple mail app is deleted. Reproduced on more than 3 iPhones - all with iOS version 14.8 or higher.
Setup: I have 3 mail apps on my device: Apple Mail, Outlook, and a third one. I never touched default mail app settings before. Then I deleted Apple Mail and Outlook was automatically set as the new default mail app in the phone settings.
Expected: When an app attempts to open the default mail app (mailto link), the Outlook app is opened.
Actual: A message pops up saying that Apple Mail app is not installed on the device.
Once I go to my phone settings and actively select Outlook or the other mail app as the default mail app, it works. Other apps open the default app and don't show the popup to install Apple Mail.
This is an issue since users will not be aware that they need to actively set an email app in their phone settings even if it already appears to be set, and appears to be unwanted behaviour.
We would love to leverage the functionality of using the phone's default mail app, but we have reproduced this issue on multiple devices and I couldn't find anything related to this issue online. Is this issue known yet? Where can I place this problem?