Asterisk on Synology DS412+

Hi, I am looking for help to configure Asterisk on Synology DS412+. I want to configure SIP and want to use through my iPhone and between my family members as well. Any help would be appriciated.

I am using it as you have described. I found the best setup to be using it as IAX rather than SIP given port issues on LAN and firewalls that you might have. Best application to use on iPhone is called Zoiper. Set it up as IAX and works like a charm.
Good luck.