It seems we need to do things as follow Add a extension target 2.use app group to share data between host app and extension 3.the content that extension print will not occur on the console unless you attach the process to it. You can also try notification I am also working on it. Good luck.

I have searched a lot，some posted 1 year ago said we need Call directory extension but it seems i only need to add this new target now. Is there any thing that i need to do out side the Device Activity Monitor extension. Thanks for your help

Thanks for your advice, i have submitted a feedback and request a TSI, but TSI replied that it was still under investigation. Would you please take a look at a sample (https://github.com/orcas1202/sample_for_TSI) Thanks in advance.

i have submited it with a sample project attached. Many thanks for your help and advice!

i have submited it with a sample project attached. Many thanks for your help and advice!

i have submited it with a sample project attached. Many thanks for your help and advice!

I have submitted it with a sample Xcode project. Many thanks for your help and advices !

I have submitted it with a sample Xcode project attached. Many thanks for your advices!