I still haven't found a solution nor received any answered on the forums where I have posted my 'dlopen' problem. Someone asked me to try a newer iPhone, so I have bought an iPhone 7. My Python-Kivy app runs without any real problems on the iPhone 7 simulator (in Xcode). But the physical iPhone 7 gives the same error as the iPhone 5s. Here is the relevant part of the log output from Xcode: Got dlopen error on Foundation: dlopen(/System/Library/Frameworks/Foundation.framework/Versions/Current/Foundation, 1): image not found Got fallback dlopen error on Foundation: dlopen(/Groups/System/Library/Frameworks/Foundation.framework/Versions/Current/Foundation, 1): image not found Traceback (most recent call last): File "/Users/henrik/geo-esp-training-ios/YourApp/main.py", line 252, in module File "/Users/henrik/geo-esp-training-ios/YourApp/main.py", line 180, in init PermissionError: [Errno 1] Operation not permitted: 'geo-esp-train.cfg' 2021-03-10 14:18:50.105679+0100 geo-esp-training[448:20514] Application quit abnormally! 2021-03-10 14:18:50.161136+0100 geo-esp-training[448:20514] Leaving Please help! It's very important that I get this app to run on iOS!

PS: It's late night here in Europe, so I will go to bed now. :-)

It's simply a filename. No path. In Android the OS automatically allocates a default folder for the app, where the file is automatically created. So I presumed that iOS works in a similar way?

That's a global string variable: configfilename = 'geo-esp-train.cfg'

It's Python. The error occurs in this file write operation statement (line 180): json.dump(self.config_data, config_file) Here is the Traceback: Traceback (most recent call last): File "/Users/henrik/geo-esp-training-ios/YourApp/main.py", line 252, in module File "/Users/henrik/geo-esp-training-ios/YourApp/main.py", line 180, in __init__ PermissionError: [Errno 1] Operation not permitted: 'geo-esp-train.cfg' 2021-02-28 23:09:59.085006+0100 geo-esp-training[457:91293] Application quit abnormally! 2021-02-28 23:09:59.294003+0100 geo-esp-training[457:91293] Leaving

I have now run my Kivy app on an iPhone 5s simulator in Xcode. That gives a slightly different error, but the app DOES run without any real problems. So the question is: How serious are these 'dlopen' errors? Here comes the slightly different error from the simulator: Got dlopen error on Foundation: dlopen(/System/Library/Frameworks/Foundation.framework/Versions/Current/Foundation, 1): no suitable image found. Did find: /System/Library/Frameworks/Foundation.framework/Versions/Current/Foundation: mach-o, but not built for iOS simulator Got fallback dlopen error on Foundation: dlopen(/Groups/System/Library/Frameworks/Foundation.framework/Versions/Current/Foundation, 1): image not found Note that I DON'T get this error: 2021-02-28 23:09:59.023510+0100 geo-esp-training[457:91731] XPC connection interrupted Note: My Mac has 29 'Foundation.framework' folders and a total of 672 '*Foundation.framework' folders... So how am I to know which folder to point to instead of the one where the 'image' is not found?