Fix Untrusted Developer

Published by @SoNiceInfo at 6/24/2020

Here is how to fix 「Untrusted Developer」.

Error Content

When you try to test an app created with Xcode on an actual device, you may see "Untrusted Developer".

Problem

This is due to iOS determining that the signature of the app is not a reliable one.
When I build the source of an app on the internet such as GitHub, I get the same alarm and cannot open it.
It's proof that Apple is preventing users from installing rogue apps.

Solution

To make the app open without this alarm, manually register it as a trustworthy one.
As shown in the above screen, go to "Settings" > "General" > "Profile" and "Trust".