What is backend of inji app, can we run backend at local ?

[sanjay95]

I am trying to run the app and have been stuck at Manifest merge error. Apart from that I am not getting how can I feed the backend believing app will communicate to some API .
Have seen this URL https://api-internal.qa4.mosip.net/ but its not live.
Is there any architecture diagram where I can visualize the communication in network

Can someone point me to clear documentation where I can find comprehensive documentation.
I am not sure what these APIs are for: https://mosip.github.io/documentation/1.2.0/1.2.0.html

I just want to run the app and see how its works with existing sandbox API and If can run the APIs at local use them in local Inji app